Process for preparing a biaryl compound

ABSTRACT

A process for preparing an optically active biaryl compound the formula (4):  
                 
 
     wherein R*, R 2 , R 3 , n 1 , n 2  and * are as defined hereinafter, which comprises reacting an aromatic sulfonic acid ester compound of the formula (1):  
                 
 
     wherein  
     R 1  is a substituted or unsubstituted alkyl or aryl group,  
     R 2  is the same or different and represents a fluorine atom, a cyano group, a nitro group, a substituted or unsubstituted linear or branched alkyl group, etc.,  
     R* is the same or different and represents a substituent having at least one asymmetric carbon, or  
     the substituents on the adjacent carbon atoms of the benzene ring may be bound each other and taken together with the benzene ring to form a fused polycyclic aromatic ring, and provided that R 1  is not a trifluoromethyl group, a nonafluorobutyl group or a pentafluorophenyl group, with an organic boron compound of the formula (2):  
                 
 
     wherein  
     R 3  is a substituted or unsubstituted aryl or heteroaryl group, and  
     Q 1  and Q 2  are the same or different and each is a hydroxyl group, an alkoxy group having 1 to 4 carbon atoms, etc., at 70° C. or below in the presence of a nickel catalyst and a base.

TECHNICAL FIELD

[0001] The present invention relates to a process for preparing anoptically active biaryl compound, which is useful as intermediates formedicaments, agrochemicals, etc.

BACKGROUND ART

[0002] As conventional processes for preparing an optically activebiaryl compound, for example, cross-coupling ofN-(t-butyloxycarbonyl)-O-(trifluoromethanesulfonyl)-tyrosine methylester which is a derivative of a natural amino acid tyrosine, withphenylboronic acid in the presence of a palladium catalyst (WO2001-36376); cross-coupling of N-FMOC-4-(trimethylstannyl)phenylalaninet-butyl ester with a halobenzene in the presence of a palladium catalyst(WO 2001-12183); cross-coupling ofN-(t-butyloxycarbonyl)-4-iodophenylalanine methyl ester withphenylboronic acid in the presence of a palladium catalyst (WO2000-43372), etc. are known.

[0003] However, the above-mentioned cross-coupling methods have problemsin the process. For example, a problem is that these methods useexpensive palladium catalysts and therefore the catalysts are requiredto be collected after the reaction. Furthermore, syntheses of reactionsubstrates are complicated because the leaving groups of the reactionsubstrates, aromatic compounds are a trifluoromethanesulfonyloxy group,which is synthesized using expensive and high caustictrifluoromethanesulfonic anhydride; a halogen, which has problematicposition selectivity for introduction onto an aromatic ring; atrimethylstannyl group, which is derived from the halogen, and the like.Therefore, these methods are not necessarily satisfactory in industry.

DISCLOSURE OF THE INVENTION

[0004] The present inventors intensively studied and found that anoptically active biaryl compound can be prepared with fine opticalpurity, by cross-coupling an aromatic sulfonic acid ester compound of aphenol compound having an optically active substituent on the aromaticring without the above-mentioned trifluoromethanesulfonyloxy group,halogen or trimethylstannyl group, with an organic boron compound usinga nickel catalyst that is more inexpensive than palladium catalysts at70° C. or below, which resulted in the completion of the presentinvention.

[0005] That is, the present invention provides a process for preparingan optically active biaryl compound of the formula (4):

[0006] wherein

[0007] R* is the same or different and represents a substituent havingat least one asymmetric carbon,

[0008] R² is the same or different and represents a fluorine atom, acyano group, a nitro group, a substituted or unsubstituted linear orbranched alkyl group, a substituted or unsubstituted cycloalkyl group, asubstituted or unsubstituted aryl or heterocyclic group, a hydroxylgroup, an alkoxyl group, an aryloxy group, an alkylthio group, anarylthio group, a protected amino group, a substituted or unsubstitutedcarbamoyl group, a substituted or unsubstituted sulfonamide group, aformyl group, an alkylcarbonyl group, an arylcarbonyl group, a carboxylgroup, an alkoxycarbonyl group, or an aryloxycarbonyl group, or

[0009] the substituents on the adjacent carbon atoms of the benzene ringmay be bound each other and taken together with the benzene ring to forma fused polycyclic aromatic ring,

[0010] R³ is a substituted or unsubstituted aryl or heteroaryl group,

[0011] n₁ is an integer of 1 to 5,

[0012] n₂ is an integer of 0 to 4, and

[0013] is as defined hereinafter,

[0014] which comprises reacting an aromatic sulfonic acid ester compoundof the formula (1):

[0015] wherein

[0016] R¹ is a substituted or unsubstituted alkyl or aryl group, and R²,R*, n₁, n₂ and * are as defined hereinabove, provided that R¹ is not atrifluoromethyl group, a nonafluorobutyl group or a pentafluorophenylgroup, with an organic boron compound of the formula (2):

[0017] wherein

[0018] R³ is as defined above, and

[0019] Q¹ and Q² are the same or different and each is a hydroxyl group,or an alkoxy group having 1 to 4 carbon atoms; or Q¹ and Q² are takentogether to form an alkylenedioxy group having 1 to 4 carbon atoms or1,2-phenylenedioxy group, which is optionally substituted with an alkylgroup having 1 to 4 carbon atoms, or

[0020] a boroxine ring compound of the formula (3):

[0021] wherein R³ is as defined hereinabove, or

[0022] a mixture of compounds of the formula (2) and the formula (3), at70° C. or below in the presence of a nickel catalyst and a base.

MODE FOR CARRYING OUT THE INVENTION

[0023] Hereinafter the present invention is explained in detail.

[0024] For the optically active aromatic sulfonic acid ester compound(1), the substituted or unsubstituted alkyl group represented by R¹includes a methyl group and an ethyl group. The unsubstituted aryl grouprepresented by R¹ includes a tolyl group such as a p-tolyl group and aphenyl group. The substituted aryl group represented by R¹ includes anitrophenyl group such as a p-nitrophenyl group. Preferred are a methylgroup, a p-tolyl group and a phenyl group. As R¹, in addition to atrifluoromethyl group, a nonafluorobutyl group ofN-acetyl-O-(nonafluorobutanesulfonyl)tyrosine methyl ester and apentafluorophenyl group ofN-acetyl-O-[(pentafluorophenyl)sulfonyl]tyrosine ethyl ester, which arerespectively disclosed in Tetrahedron Lett. 1999, 40, 7469-7472 andAnal. Chem., 1984, 56, 2512-2517 are known, but for the presentinvention, it is not necessary that R¹ is such an expensivefluorine-substituted group.

[0025] For the optically active aromatic sulfonic acid ester compound(1) and the optically active biaryl compound (4), the substituentsrepresented by R² are explained hereinafter.

[0026] The unsubstituted alkyl group includes linear or branched alkylgroups such as a methyl group, an ethyl group, a propyl group, a butylgroup and an isopropyl group, and cycloalkyl groups such as acyclopropyl group, a cyclobutyl group, a cyclopentyl group and acyclohexyl group. The substituted alkyl group includes haloalkyl groupssuch as a trifluoromethyl group.

[0027] The substituted or unsubstituted heterocyclic group includes apyridyl group, a quinazolinyl group, a pyrimidyl group, a furyl group, athienyl group, a pyrrolyl group and a imidazolyl group. The substitutedor unsubstituted aryl group includes a phenyl group and a naphthylgroup.

[0028] The alkoxy group includes a methoxy group and an ethoxy group.

[0029] The aryloxy group includes a phenoxy group.

[0030] The alkylthio group includes a methylthio group and an ethylthiogroup.

[0031] The arylthio group includes a phenylthio group.

[0032] The protected amino group includes a t-butyloxycarbonylaminogroup protected with a t-butyloxycarbonyl group, etc.

[0033] The substituted or unsubstituted sulfonamide group includes abenzenesulfonamide group and a methanesulfonamide group.

[0034] The substituted or unsubstituted alkoxycarbonyl group includes amethoxycarbonyl group, an ethoxycarbonyl group and a benzyloxycarbonylgroup.

[0035] The substituted or unsubstituted carbamoyl group includes acarbamoyl group and a N-phenylcarbamoyl group.

[0036] The substituted or unsubstituted aryloxycarbonyl group includes aphenoxycarbonyl group and a p-methoxyphenoxycarbonyl group.

[0037] In the optically active aromatic sulfonic acid ester compound (1)and optically active biaryl compound (4), the optically activesubstituent R* is a substituent having at least one asymmetric carbon,and the specific example includes a group of the formula (5):

[0038] wherein R⁴, R⁵ and R⁶ are different and each is a hydrogen atom,a fluorine atom, a substituted or unsubstituted linear or branched alkylgroup, a substituted or unsubstituted cycloalkyl group, a hydroxylgroup, a substituted or unsubstituted alkoxyl group, a substituted orunsubstituted aryloxy group, a cyano group, a protected amino group, aformyl group, a carboxyl group, a substituted or unsubstitutedalkoxycarbonyl group, a substituted or unsubstituted aryloxycarbonylgroup, a substituted or unsubstituted carbamoyl group, a substituted orunsubstituted heterocyclic group, or a substituted or unsubstituted arylgroup,

[0039] A is a substituted or unsubstituted alkylene group, a substitutedor unsubstituted nitrogen atom, oxygen atom or sulfur atom,

[0040] n₃ is an integer of 0 or 1, and

[0041] the carbon atom marked with * is an asymmetric carbon atom.

[0042] Hereinafter R⁴, R⁵ and R⁶ of the formula (5) are explained indetail. The substituted or unsubstituted linear or branched alkyl groupand substituted or unsubstituted cycloalkyl group include linear orbranched alkyl groups such as a methyl group, an ethyl group, a propylgroup, a butyl group and an isopropyl group, and cycloalkyl groups suchas a cyclopropyl group, a cyclobutyl group, a cyclopentyl group and acyclohexyl group, and further include halogen-substituted alkyl groupssuch as a trifluoromethyl group.

[0043] The substituted or unsubstituted alkoxy group includes a methoxygroup and an ethoxy group.

[0044] The substituted or unsubstituted aryloxy group includes a phenoxygroup.

[0045] The protected amino group includes a t-butyloxycarbonylaminogroup, and an amino group protected by a protecting group for an aminogroup as described below.

[0046] The substituted or unsubstituted alkoxycarbonyl group includes amethoxycarbonyl group, an ethoxycarbonyl group and a benzyloxycarbonylgroup.

[0047] The substituted or unsubstituted aryloxycarbonyl group includes aphenoxycarbonyl group and a p-methoxyphenoxycarbonyl group.

[0048] The substituted or unsubstituted carbamoyl group includes acarbamoyl group and an N-phenylcarbamoyl group.

[0049] The substituted or unsubstituted heterocyclic group includes apyridyl group, a quinazolinyl group, a pyrimidyl group, a furyl group, athienyl group, a pyrrolyl group and an imidazolyl group.

[0050] The substituted or unsubstituted aryl group includes a phenylgroup, a tolyl group and a naphthyl group.

[0051] The substituted or unsubstituted alkylene group represented by Aincludes alkylene groups having 1 to 4 carbon atoms, more specifically—CH₂—, —CH₂CH₂—, —C(CH₃)₂—, etc.

[0052] The substituted or unsubstituted nitrogen atom represented by Aincludes —NH—, —N(CH₃)—, etc.

[0053] The optically active substituent of the formula (5) includes asubstituent of the formula (5′):

[0054] wherein

[0055] R¹¹ is a protecting group for an amino group,

[0056] R¹² is a protecting group for an amino group or a hydrogen atom,

[0057] R¹³ is a substituted or unsubstituted alkyl group, or either R¹¹or R¹² and R¹³ are taken together to represent a protecting group foramino acid,

[0058] n₁₁, n₁₂ and n₁₃ are each independently an integer of 0 or 1, and

[0059] the carbon atom marked with * is an asymmetric carbon atom.

[0060] More specifically, a compound of the formula (1a)

[0061] wherein R¹¹, R¹², R¹³ and n₁₁, n₁₂, n₁₃ and * are as definedhereinabove, and R¹⁰ is as defined for R¹, which corresponds to acompound of the formula (1) wherein n₁=1 and n₂=0, is exemplified.

[0062] For the amino acid compound of the formula (1a), R¹¹ and R¹², theprotecting groups for an amino group, include carbamate typeamino-protecting groups such as a substituted or unsubstitutedalkyloxycarbonyl group (wherein the substituent includes an alkylsilylgroup, a substituted or unsubstituted aryl group, a halogen atom, asubstituted or unsubstituted heterocyclic group, a bridged cyclichydrocarbon group, an acyl group, an alkylthio group, adicyclohexylcarboxyamide group, a substituted or unsubstitutedbenzenesulfonyl group, an alkylsulfonyl group, a substituted orunsubstituted phosphonio group, a cyano group, etc.), a substituted orunsubstituted alkenyloxycarbonyl group (wherein the substituent includesan aryl group, a nitro group, etc.), a substituted or unsubstitutedaryloxycarbonyl group, a substituted or unsubstituted heterocyclicoxycarbonyl group and a substituted or unsubstituted alkyldithiocarbonyl group, amide type amino-protecting groups, and N-alkyltype amino-protecting groups.

[0063] The substituted or unsubstituted alkyloxycarbonyl groupspecifically includes a methyloxycarbonyl group, an ethyloxycarbonylgroup, an isobutyloxycarbonyl group, a t-butyloxycarbonyl group, at-amyloxycarbonyl group, a 2,2,2-trichloroethyloxycarbonyl group, a2-trimethylsilylethyloxycarbonyl group, a phenylethyloxycarbonyl group,a 1-(1-adamantyl)-1-methylethyloxycarbonyl group, a1,1-dimethyl-2-haloethyloxycarbonyl group, a1,1-dimethyl-2,2-dibromoethyloxycarbonyl group, a1,1-dimethyl-2,2,2-trichloroethyloxycarbonyl group, a1-methyl-1-(4-biphenylyl)ethyloxycarbonyl group, a1-(3,5-di-t-butylphenyl)-1-methylethyloxycarbonyl group, a2-(2′-pyridyl)ethyloxycarbonyl group, a 2-(4′-pyridyl)ethyloxycarbonylgroup, a 2-(N,N-dicyclohexylcarboxyamide)ethyloxycarbonyl group, a1-adamantyloxycarbonyl group, a benzyloxycarbonyl group, ap-methoxybenzyloxycarbonyl group, a p-nitrobenzyloxycarbonyl group, ap-bromobenzyloxycarbonyl group, a p-chlorobenzyloxycarbonyl group, a2,4-dichlorobenzyloxycarbonyl group, a 4-methylsulfinylbenzyloxycarbonylgroup, a 9-anthrylmethyloxycarbonyl group, a diphenylmethyloxycarbonylgroup, a 9-fluorenylmethyloxycarbonyl group, a9-(2,7-dibromo)fluorenylmethyloxycarbonyl group, a2,7-di-t-butyl-[9-(10,10-dioxo-thioxanthyl)]methyloxycarbonyl group, a4-methoxyphenacyloxycarbonyl group, a 2-methylthioethyloxycarbonylgroup, a 2-methylsulfonylethyloxycarbonyl group, a2-(p-toluenesulfonyl)ethyloxycarbonyl group, a[2-(1,3-dithianyl)]methyloxycarbonyl group, a4-methylthiophenyloxycarbonyl group, a 2,4-dimethylthiophenyloxycarbonylgroup, a 2-phosphonioethyloxycarbonyl group, a2-triphenylphosphonioisopropyloxycarbonyl group, a1,1-dimethyl-2-cyanoethyloxycarbonyl group, am-chloro-p-acyloxybenzyloxycarbonyl group, ap-(dihydroxyboryl)benzyloxycarbonyl group, a5-benzoisoxazolylmethyloxycarbonyl group, a2-(trifluoromethyl)-6-chromonylmethyloxycarbonyl group, a3,5-dimethoxybenzyloxycarbonyl group, a o-nitrobenzyloxycarbonyl group,a 3,4-dimethoxy-6-nitrobenzyloxycarbonyl group, and aphenyl(o-nitrophenyl)methyloxycarbonyl group.

[0064] The substituted or unsubstituted alkenyloxycarbonyl groupincludes a vinyloxycarbonyl group, an allyloxycarbonyl group, a1-isopropylallyloxycarbonyl group, a cinnamyloxycarbonyl group and a4-nitrocinnamyloxycarbonyl group.

[0065] The substituted or unsubstituted heterocyclic oxycarbonyl groupincludes an 8-quinolyloxycarbonyl group and an N-piperidinyloxycarbonylgroup.

[0066] The substituted or unsubstituted aryloxycarbonyl group includes aphenyloxycarbonyl group and an m-nitrophenyloxycarbonyl group.

[0067] The amide type amino-protecting group includes a formyl group, anacetyl group, a chloroacetyl group, a trichloroacetyl group, atrifluoroacetyl group, a phenylacetyl group and a benzoyl group.

[0068] The N-alkyl type amino-protecting group includes a benzyl group,an N-di(4-methoxyphenyl)methyl group, an N-5-dibenzosuberyl group, anN-triphenylmethyl group, a (4-methoxyphenyl)diphenylmethyl group, anN-9-phenylfluorenyl group, an allyl group, anN-[2-(trimethylsilyl)ethoxy]methyl group and an N-3-acetoxypropyl group.

[0069] The substituted or unsubstituted alkyl group represented by R¹³includes a methyl group, an ethyl group, an n-propyl group, an isopropylgroup, an n-butyl group, an isobutyl group, an s-butyl group, a t-butylgroup, a cyclohexyl group, a 9-fluorenylmethyl group, a methoxymethylgroup, a benzyloxymethyl group, a pivaloyloxymethyl group, aphenylacetoxymethyl group and an N-phthalimidomethyl group, preferably aC1 to C4 alkyl group, and further includes aralkyl groups such as abenzyl group, an α-phenethyl group, a triphenylmethyl group, adiphenylmethyl group, an o-nitrobenzyl group, a p-nitrobenzyl group, ap-methoxybenzyl group and a 2,6-dimethoxybenzyl group, preferably abenzyl group.

[0070] The protection of the amino acid formed by either R¹¹ or R¹²taken together with R¹³ includes formation of a cyclic structure such as4-substituted-5-oxo-1,3-oxazolidine,4-substituted-2-methyl-5(4H)-oxazolone,4-substituted-2,5-oxazolidinedione or5-substituted-2,4-imidazolidinedione by reaction of an amino group andcarboxyl group of the amino acid compound of the formula (1a) with aprotecting agent.

[0071] R¹⁰ is a substituted or unsubstituted alkyl or aryl group otherthan a fluorine-substituted alkyl or aryl group. The unsubstituted alkylgroup includes a methyl group, an ethyl group, an n-propyl group, anisopropyl group, an n-butyl group, an isobutyl group, a s-butyl groupand a t-butyl group, and preferably includes a methyl group. Thesubstituted or unsubstituted aryl group includes a phenyl group, ap-methylphenyl group, a p-ethylphenyl group, a 3-nitrophenyl group, a1-naphthyl group and a 2-naphthyl group, and preferably includes aphenyl group, a p-nitrophenyl group and p-methylphenyl group.

[0072] The compound of the formula (1a) wherein R¹¹ is a carbamate typeamino-protecting group, an amide type amino-protecting group or anN-alkyl amino-protecting group and R¹² is a hydrogen atom is preferred.The compound of the formula (1a) wherein R¹¹ is an acetyl group, atrifluoroacetyl group, a benzyl group, a t-butyloxycarbonyl group, a9-fluorenylmethoxycarbonyl group or a benzyloxycarbonyl group and R¹² isa hydrogen atom is more preferred.

[0073] The compound of the formula (1) can be prepared by, for example,reacting a phenol compound of the formula (6):

[0074] wherein R*, R², n₁ and n₂ are as defined hereinabove, with asulfonic acid halide or the corresponding sulfonic acid anhydride, whichis a reactive derivative of R¹SO₃H, in the presence of a base (forexample, a method described in the Chemical Society of Japan, ed.,“Shinjikken Kagaku Koza 14, Synthesis and Reaction of Organic Compounds(III)”, Maruzen Co., Ltd., 1978.) More specifically, it can be producedby the sulfonation step (C) as described below using the phenol compoundof the formula (6) as a starting material. Although a method ofpreparing the compound of the formula (6) is not specifically limited,many of the compounds are available as a commercial product.Alternatively, the compound can be prepared by optically activating thecorresponding racemate available as a commercial product by opticalresolution, etc.

[0075] Furthermore, the compound of the formula (1a) can be prepared,for example, by subjecting the optically active compound of the formula(6a):

[0076] wherein R¹¹, R¹², R¹³, n₁₁, n₁₂, n₁₃ and * are as definedhereinabove, to a reaction similar to the reaction described above forthe compound of the formula (6).

[0077] The compound of the formula (6a) can be prepared by carrying outby the carboxyl group-protecting step (A), the amino group-protectingstep (B) and the sulfonic acid esterification step (C) as describedbelow, using an aromatic amino acid having a hydroxyl group on thearomatic ring of the formula (12):

[0078] wherein n₁₁, n₁₂, n₁₃ and * are as defined hereinabove, as astarting material. Many of the compounds of the formula (12) areavailable as a commercial product. Alternatively, the compound can beprepared by optically activating the corresponding racemate available asa commercial product by optical resolution, etc. Moreover, the compoundcan be also prepared from the corresponding aldehyde compound and halideaccording to a method described in, for example, Chemical Society ofJapan, ed., “Jikken Kagaku Koza 22, Organic Synthesis IV, Acid, AminoAcid and Peptide”, 4^(th) edition, Maruzen Co., Ltd., 1992, pp. 193-214.

[0079] The steps (A), (B) and (C) can be carried out in any order.Alternatively, two or three of these steps can be carried outsimultaneously depending on reagents to be used.

[0080] (A) Carboxyl Group-Protecting Step

[0081] An amino acid ester compound is obtained by, for example,reacting an aromatic amino acid having a hydroxyl group on the aromaticring or a salt thereof with an alcohol compound of the formula (13):R¹³OH wherein R¹³ is a substituted or unsubstituted alkyl group, in thepresence of an esterifying agent. The amino group portion of the aminoacid ester compound may be free or may be in the form of an acid saltsuch as hydrochloride, methanesulfonate, p-toluenesulfonate orbenzenesulfonate. The alcohol compound (13) used herein includesmethanol, ethanol, n-propanol, isopropanol, n-butanol, sec-butanol,t-butanol and benzylalcohol. The amount used of the alcohol compound isusually from about 1 mol to 40 mol, preferably from about 10 mol to 30mol relative to 1 mol of the substrate. The esterifying agent includeschlorinating agents such as thionyl chloride and phosphorus oxychloride.The amount used of the esterifying agent is usually from about 1 mol to5 mol, preferably from about 1 mol to 2 mol relative to 1 mol of thesubstrate. In addition, an organic solvent may be added to the reaction,if necessary. The reaction temperature is usually in the range from −20°C. to the reflux temperature of the reaction mixture, preferably in therange of about 0° C. to 60° C. After the reaction is completed, thereaction mass is optionally concentrated, and an organic solvent such astoluene is optionally added to the reaction mass to give an acid salt ofthe desired amino acid ester compound.

[0082] (B) Amino Group-Protecting Step

[0083] An amino acid ester compound in which a protectiing group for anamino group represented by R¹¹ or R¹² has been introduced is obtainedby, for example, reacting the amino acid ester compound or an acid saltthereof with a protecting agent for an amino group in the presence of abase. The protecting agent used herein may be any protecting agent thatprovides the above-mentioned groups exemplified as a protecting groupfor an amino group. For introduction of the representative protectinggroup R¹¹ or R¹², specific examples of a protecting agent include acylhalides such as acetyl chloride and di-t-butylcarbonate.

[0084] The amount used of the protecting agent is usually from 1 mol to10 mol, preferably from about 1 mol to 3 mol relative to 1 mol of thesubstrate.

[0085] The base used in the above reaction includes organic bases suchas triethylamine and pyridine, and inorganic bases such as sodiumhydroxide. The amount used of the base is usually from about 0.1 mol to2 mol relative to 1 mol of the substrate.

[0086] In the above reaction, an organic solvent is usually used. Such asolvent includes hydrocarbon solvents such as n-hexane, cyclohexane,n-pentane, toluene and xylene, ether solvents such as diethylether,tetrahydrofuran and dioxane, ester solvents such as ethyl acetate andbutyl acetate, halogen solvents such as chloroform, dichloromethane,monochlorobenzene and o-dichlorobenzene, and aprotic polar solvents suchas N,N-dimethylformamide, dimethylsulfoxide and N,N-dimethylacetamide.

[0087] The reaction temperature is usually in the range from thefreezing point of the reaction system to the boiling point of a solventused, preferably in the range of −20° C. to 40° C.

[0088] After the reaction, the desired amino group-protected amino acidester compound can be obtained by a conventional post-treatment.

[0089] Alternatively, a carboxyl group and an amino group of an aromaticamino acid having a hydroxyl group on the aromatic ring can be protectedsimultaneously. For example, the carboxyl group and amino group of anaromatic α-amino acid having a hydroxyl group on the aromatic ring canbe protected simultaneously by a reaction with formaldehyde, aceticanhydride and thionyl chloride to give a4-substituted-5-oxo-1,3-oxazolidine compound. A reagent forsimultaneously protecting a carboxyl group and an amino group includesphosgene and urea. The amount used of the reagent is usually from about1 mol to 10 mol, preferably about 1 mol to 3 mol relative to 1 mol ofthe substrate.

[0090] In the above reaction, an organic solvent is usually used. Such asolvent includes hydrocarbon solvents such as n-hexane, cyclohexane,n-pentane, toluene and xylene, ether solvents such as diethylether,tetrahydrofuran and dioxane, ester solvents such as ethyl acetate andbutyl acetate, halogen solvents such as chloroform, dichloromethane,monochlorobenzene and o-dichlorobenzene, and aprotic polar solvents suchas N,N-dimethylformamide, dimethylsulfoxide and N,N-dimethylacetamide.

[0091] The reaction temperature is usually in the range from thefreezing point of the reaction system to the boiling point of a solventused, preferably in the range of about −20° C. to 40° C.

[0092] After the reaction, the desired amino acid compound in which thecarboxyl group and amino group have been simultaneously protected can beobtained by a conventional post-treatment.

[0093] (C) Sulfonic Esterification Step

[0094] The aromatic sulfonic acid ester compound of the formula (1) isobtained by, for example, reacting the phenol compound of the formula(6) or an amino group-protected amino acid ester compound with asulfonic acid esterifying agent in the presence of a base. The sulfonicacid esterifying agent used herein includes sulfonic acid halide of theformula R¹SO₂X or R¹⁰SO₂X wherein X is a halogen atom or R¹SO₃ orR¹⁰SO₃, for example, sulfonic acid chloride such as p-toluenesulfonylchloride and methanesulfonyl chloride, and sulfonic anhydrides such asp-toluenesulfonic anhydride and methanesulfonic anhydride. The amountused of the sulfonic acid esterifying agent is usually from about 1 molto 3 mol relative to 1 mol of the substrate. The base used includesorganic bases such as triethylamine and pyridine, and inorganic basessuch as sodium hydroxide. The amount used of the base is usually fromabout 1 mol to 3 mol per 1 mol of the substrate.

[0095] In the above reaction, an organic solvent is usually used. Such asolvent includes hydrocarbon solvents such as n-hexane, cyclohexane,n-pentane, toluene and xylene, ether solvents such as diethyl ether,tetrahydrofuran and dioxane, ester solvents such as ethyl acetate andbutyl acetate, halogen solvents such as chloroform, dichloromethane,monochlorobenzene and o-dichlorobenzene, and aprotic polar solvents suchas N,N-dimethylformamide, dimethylsulfoxide and N,N-dimethylacetamide.

[0096] The reaction temperature is usually in the range from thefreezing point of the reaction system to the boiling point of a solventused, preferably in the range of about −20° C. to 40° C.

[0097] After the reaction, the desired aromatic sulfonic acid estercompound of the formula (1) can be obtained by conventionalpost-treatment.

[0098] Specific examples of the aromatic sulfonic acid ester compound ofthe formula (1) of the present invention include the optically activeforms of the following compounds.

[0099] 2-(4-(p-tosluenesulfonyloxy)phenyl)butane,2-(4-methanesulfonyloxyphenyl)butane,2-(4-benzenesulfonyloxyphenyl)butane,

[0100] 2-(4-(p-toluenesulfonyloxy)phenyl)pentane,2-(4-methanesulfonyloxyphenyl)pentane,2-(4-benzenesulfonyloxyphenyl)pentane,

[0101] 2-methyl-3-(4-(p-toluenesulfonyloxy)phenyl)butane,2-methyl-3-(4-methanesulfonyloxyphenyl)butane,2-methyl-3-(4-benzenesulfonyloxyphenyl)butane,

[0102] 2-(3-(p-toluenesulfonyloxy)phenyl)butane,2-(3-methanesulfonyloxyphenyl)butane,2-(3-benzenesulfonyloxyphenyl)butane,

[0103] 2-(3-(p-toluenesulfonyloxy)phenyl)pentane,2-(3-methanesulfonyloxyphenyl)pentane,2-(3-benzenesulfonyloxyphenyl)pentane,

[0104] 2-(2-(p-toluenesulfonyloxy)phenyl)butane,2-(2-methanesulfonyloxyphenyl)butane,2-(2-benzenesulfonyloxyphenyl)butane,

[0105] 2-(2-(p-toluenesulfonyloxy)phenyl)pentane,2-(2-methanesulfonyloxyphenyl)pentane,2-(2-benzenesulfonyloxyphenyl)pentane,

[0106] 2-methyl-3-(2-(p-toluenesulfonyloxy)phenyl)butane,2-methyl-3-(2-methanesulfonyloxyphenyl)butane,2-methyl-3-(2-benzenesulfonyloxyphenyl)butane,

[0107] 1-phenyl-1-(4-(p-toluenesulfonyloxy)phenyl)ethane,1-phenyl-1-(4-methanesulfonyloxyphenyl)ethane,1-phenyl-1-(4-benzenesulfonyloxyphenyl)ethane,

[0108] 1-phenyl-1-(4-(p-toluenesulfonyloxy)phenyl)propane,1-phenyl-1-(4-methanesulfonyloxyphenyl)propane,1-phenyl-1-(4-benzenesulfonyloxyphenyl)propane,

[0109] 2-methyl-1-phenyl-1-(4-(p-toluenesulfonyloxy)phenyl)propane,2-methyl-1-phenyl-1-(4-methanesulfonyloxyphenyl)propane,2-methyl-1-phenyl-1-(4-benzenesulfonyloxyphenyl)propane,2,2-dimethyl-1-phenyl-1-(4-(p-toluenesulfonyloxy)phenyl)propane,2,2-dimethyl-1-phenyl-1-(4-methanesulfonyloxyphenyl)propane,2,2-dimethyl-1-phenyl-1-(4-benzenesulfonyloxyphenyl)propane,

[0110] 1-phenyl-1-(2-(p-toluenesulfonyloxy)phenyl)ethane,1-phenyl-1-(2-methanesulfonyloxyphenyl)ethane,1-phenyl-1-(2-benzenesulfonyloxyphenyl)ethane,

[0111] 1-phenyl-1-(2-(p-toluenesulfonyloxy)phenyl)propane,1-phenyl-1-(2-methanesulfonyloxyphenyl)propane,1-phenyl-1-(2-benzenesulfonyloxyphenyl)propane,

[0112] 2-methyl-1-phenyl-1-(2-(p-toluenesulfonyloxy)phenyl)propane,2-methyl-1-phenyl-1-(2-methanesulfonyloxyphenyl)propane,2-methyl-1-phenyl-1-(2-benzenesulfonyloxyphenyl)propane,2,2-dimethyl-1-phenyl-1-(2-(p-toluenesulfonyloxy)phenyl)propane,2,2-dimethyl-1-phenyl-1-(2-methanesulfonyloxyphenyl)propane,2,2-dimethyl-1-phenyl-1-(2-benzenesulfonyloxyphenyl)propane,

[0113] 2-methyl-2-(4-(p-toluenesulfonyloxy)phenyl)acetaldehyde,2-methyl-2-(3-(p-toluenesulfonyloxy)phenyl)acetaldehyde,2-methyl-2-(2-(p-toluenesulfonyloxy)phenyl)acetaldehyde,2-methyl-2-(4-methanesulfonyloxyphenyl)acetaldehyde,2-methyl-2-(3-methanesulfonyloxyphenyl)acetaldehyde,2-methyl-2-(2-methanesulfonyloxyphenyl)acetaldehyde,2-methyl-2-(4-benzenesulfonyloxyphenyl)acetaldehyde,2-methyl-2-(3-benzenesulfonyloxyphenyl)acetaldehyde,2-methyl-2-(2-benzenesulfonyloxyphenyl)acetaldehyde,3-(4-(p-toluenesulfonyloxy)phenyl)-2-butanone,3-(3-(p-toluenesulfonyloxy)phenyl)-2-butanone,3-(4-methanesulfonyloxyphenyl)-2-butanone,3-(3-methanesulfonyloxyphenyl)-2-butanone,3-(4-benzenesulfonyloxyphenyl)-2-butanone,3-(3-benzenesulfonyloxyphenyl)-2-butanone,

[0114] 2-methyl-2-(4-(p-toluenesulfonyloxy)phenyl)acetonitrile,2-methyl-2-(2-(p-toluenesulfonyloxy)phenyl)acetonitrile,2-methyl-2-(4-methanesulfonyloxyphenyl)acetonitrile,2-methyl-2-(2-methanesulfonyloxyphenyl)acetonitrile,2-methyl-2-(4-benzenesulfonyloxyphenyl)acetonitrile,2-methyl-2-(2-benzenesulfonyloxyphenyl)acetonitrile,2-(4-(p-toluenesulfonyloxy)phenyl)propanoic acid methyl ester,2-(3-(p-toluenesulfonyloxy)phenyl)propanoic acid methyl ester,2-(2-(p-toluenesulfonyloxy)phenyl)propanoic acid methyl ester,2-(4-methanesulfonyloxyphenyl)propanoic acid methyl ester,2-(3-methanesulfonyloxyphenyl)propanoic acid methyl ester,2-(2-methanesulfonyloxyphenyl)propanoic acid methyl ester,2-(4-benzenesulfonyloxyphenyl)propanoic acid methyl ester,2-(3-benzenesulfonyloxyphenyl)propanoic acid methyl ester,2-(2-benzenesulfonyloxyphenyl)propanoic acid methyl ester,

[0115] 2-(4-(p-toluenesulfonyloxy)phenyl)propanoic acid ethyl ester,2-(3-(p-toluenesulfonyloxy)phenyl)propanoic acid ethyl ester,2-(2-(p-toluenesulfonyloxy)phenyl)propanoic acid ethyl ester,2-(4-methanesulfonyloxyphenyl)propanoic acid ethyl ester,2-(3-methanesulfonyloxyphenyl)propanoic acid ethyl ester,2-(2-methanesulfonyloxyphenyl)propanoic acid ethyl ester,2-(4-benzenesulfonyloxyphenyl)propanoic acid ethyl ester,2-(3-benzenesulfonyloxyphenyl)propanoic acid ethyl ester,2-(2-benzenesulfonyloxyphenyl)propanoic acid ethyl ester,

[0116] 2-(4-(p-toluenesulfonyloxy)phenyl)propanoic acid (t-butyl) ester,2-(3-(p-toluenesulfonyloxy)phenyl)propanoic acid (t-butyl) ester,2-(2-(p-toluenesulfonyloxy)phenyl)propanoic acid (t-butyl) ester,2-(4-methanesulfonyloxyphenyl)propanoic acid (t-butyl) ester,2-(3-methanesulfonyloxyphenyl)propanoic acid (t-butyl) ester,2-(2-methanesulfonyloxyphenyl)propanoic acid (t-butyl) ester,2-(4-benzenesulfonyloxyphenyl)propanoic acid (t-butyl) ester,2-(3-benzenesulfonyloxyphenyl)propanoic acid (t-butyl) ester,2-(2-benzenesulfonyloxyphenyl)propanoic acid (t-butyl) ester,

[0117] 2-(4-(p-toluenesulfonyloxy)phenyl)propanoic acid benzyl ester,2-(3-(p-toluenesulfonyloxy)phenyl)propanoic acid benzyl ester,2-(2-(p-toluenesulfonyloxy)phenyl)propanoic acid benzyl ester,2-(4-methanesulfonyloxyphenyl)propanoic acid benzyl ester,2-(3-methanesulfonyloxyphenyl)propanoic acid benzyl ester,2-(2-methanesulfonyloxyphenyl)propanoic acid benzyl ester,2-(4-benzenesulfonyloxyphenyl)propanoic acid benzyl ester,2-(3-benzenesulfonyloxyphenyl)propanoic acid benzyl ester,2-(2-benzenesulfonyloxyphenyl)propanoic acid benzyl ester,

[0118] 2-(4-(p-toluenesulfonyloxy)phenyl)butanoic acid methyl ester,2-(2-(p-toluenesulfonyloxy)phenyl)butanoic acid methyl ester,2-(4-methanesulfonyloxyphenyl)butanoic acid methyl ester,2-(2-methanesulfonyloxyphenyl)butanoic acid methyl ester,2-(4-benzenesulfonyloxyphenyl)butanoic acid methyl ester,2-(2-benzenesulfonyloxyphenyl)butanoic acid methyl ester,

[0119] 3-methyl-2-(4-(p-toluenesulfonyloxy)phenyl)butanoic acid methylester, 3-methyl-2-(3-(p-toluenesulfonyloxy)phenyl)butanoic acid methylester, 3-methyl-2-(4-methanesulfonyloxyphenyl)butanoic acid methylester, 3-methyl-2-(3-methanesulfonyloxyphenyl)butanoic acid methylester, 3-methyl-2-(4-benzenesulfonyloxyphenyl)butanoic acid methylester, 3-methyl-2-(3-benzenesulfonyloxyphenyl)butanoic acid methylester,

[0120] 2-methyl-2-(4-(p-toluenesulfonyloxy)phenyl)acetamide,2-methyl-2-(3-(p-toluenesulfonyloxy)phenyl)acetamide,2-methyl-2-(4-methanesulfonyloxyphenyl)acetamide,2-methyl-2-(3-methanesulfonyloxyphenyl)acetamide,2-methyl-2-(4-benzenesulfonyloxyphenyl)acetamide,

[0121] 2-methyl-2-(3-benzenesulfonyloxyphenyl)acetamide,4-(p-toluenesulfonyloxy)-α-methylbenzylalcohol,4-methanesulfonyloxy-α-methylbenzylalcohol,4-benzenesulfonyloxy-α-methylbenzylalcohol,4-(p-toluenesulfonyloxy)-α-methylbenzylalcohol methyl ether,4-methanesulfonyloxy-α-methylbenzylalcohol methyl ether,4-benzenesulfonyloxy-α-methylbenzylalcohol methyl ether,4-(p-toluenesulfonyloxy)-α-methylbenzylalcohol benzyl ether,4-methanesulfonyloxy-α-methylbenzylalcohol benzyl ether,4-benzenesulfonyloxy-α-methylbenzylalcohol benzyl ether,4-(p-toluenesulfonyloxy)-α-methylbenzylalcohol trimethylsilyl ether,4-methanesulfonyloxy-α-methylbenzylalcohol trimethylsilyl ether,4-benzenesulfonyloxy-α-methylbenzylalcohol trimethylsilyl ether,

[0122] 4-(p-toluenesulfonyloxy)-α-methylbenzyl acetate,4-methanesulfonyloxy-α-methylbenzyl acetate,4-benzenesulfonyloxy-α-methylbenzyl acetate,3-(p-toluenesulfonyloxy)-α-methylbenzylalcohol,3-methanesulfonyloxy-α-methylbenzylalcohol,3-benzenesulfonyloxy-α-methylbenzylalcohol,3-(p-toluenesulfonyloxy)-α-methylbenzylalcohol methyl ether,3-methanesulfonyloxy-α-methylbenzylalcohol methyl ether,3-benzenesulfonyloxy-α-methylbenzylalcohol methyl ether,

[0123] 3-(p-toluenesulfonyloxy)-α-methylbenzylalcohol benzyl ether,3-methanesulfonyloxy-α-methylbenzylalcohol benzyl ether,3-benzenesulfonyloxy-α-methylbenzylalcohol benzyl ether,3-(p-toluenesulfonyloxy)-α-methylbenzylalcohol trimethylsilyl ether,3-methanesulfonyloxy-α-methylbenzylalcohol trimethylsilyl ether,3-benzenesulfonyloxy-α-methylbenzylalcohol trimethylsilyl ether,

[0124] 3-(p-toluenesulfonyloxy)-α-methylbenzyl acetate,3-methanesulfonyloxy-α-methylbenzyl acetate,3-benzenesulfonyloxy-α-methylbenzyl acetate,2-(p-toluenesulfonyloxy)-α-methylbenzylalcohol,2-methanesulfonyloxy-α-methylbenzylalcohol,2-benzenesulfonyloxy-α-methylbenzylalcohol,

[0125] 2-(p-toluenesulfonyloxy)-α-methylbenzylalcohol methyl ether,2-methanesulfonyloxy-α-methylbenzylalcohol methyl ether,2-benzenesulfonyloxy-α-methylbenzylalcohol methyl ether,

[0126] 2-(p-toluenesulfonyloxy)-α-methylbenzylalcohol benzyl ether,2-methanesulfonyloxy-α-methylbenzylalcohol benzyl ether,2-benzenesulfonyloxy-α-methylbenzylalcohol benzyl ether,

[0127] 2-(p-toluenesulfonyloxy)-α-methylbenzylalcohol trimethylsilylether, 2-methanesulfonyloxy-α-methylbenzylalcohol trimethylsilyl ether,2-benzenesulfonyloxy-α-methylbenzylalcohol trimethylsilyl ether,

[0128] 2-(p-toluenesulfonyloxy)-α-methylbenzyl acetate,2-methanesulfonyloxy-α-methylbenzyl acetate,2-benzenesulfonyloxy-α-methylbenzyl acetate,4-(p-toluenesulfonyloxy)-α-isopropylbenzylalcohol,4-methanesulfonyloxy-α-isopropylbenzylalcohol,4-benzenesulfonyloxy-α-isopropylbenzylalcohol,4-(p-toluenesulfonyloxy)-α-isopropylbenzylalcohol methyl ether,4-methanesulfonyloxy-α-isopropylbenzylalcohol methyl ether,4-benzenesulfonyloxy-α-isopropylbenzylalcohol methyl ether,

[0129] 4-(p-toluenesulfonyloxy)-α-isopropylbenzylalcohol benzyl ether,4-methanesulfonyloxy-α-isopropylbenzylalcohol benzyl ether,4-benzenesulfonyloxy-α-isopropylbenzylalcohol benzyl ether,

[0130] 4-(p-toluenesulfonyloxy)-α-isopropylbenzylalcohol trimethylsilylether, 4-methanesulfonyloxy-α-isopropylbenzylalcohol trimethylsilylether, 4-benzenesulfonyloxy-α-isopropylbenzylalcohol trimethylsilylether,

[0131] 4-(p-toluenesulfonyloxy)-α-isopropylbenzyl acetate,4-methanesulfonyloxy-α-isopropylbenzyl acetate,4-benzenesulfonyloxy-α-isopropylbenzyl acetate,4-(p-toluenesulfonyloxy)-α-(t-butyl)benzylalcohol,4-methanesulfonyloxy-α-(t-butyl)benzylalcohol,4-benzenesulfonyloxy-α-(t-butyl)benzylalcohol,

[0132] 4-(p-toluenesulfonyloxy)-α-(t-butyl)benzylalcohol methyl ether,4-methanesulfonyloxy-α-(t-butyl)benzylalcohol methyl ether,4-benzenesulfonyloxy-α-(t-butyl)benzylalcohol methyl ether,

[0133] 4-(p-toluenesulfonyloxy)-α-(t-butyl)benzylalcohol benzyl ether,4-methanesulfonyloxy-α-(t-butyl)benzylalcohol benzyl ether,4-benzenesulfonyloxy-α-(t-butyl)benzylalcohol benzyl ether,

[0134] 4-(p-toluenesulfonyloxy)-α-(t-butyl)benzylalcohol trimethylsilylether, 4-methanesulfonyloxy-α-(t-butyl)benzylalcohol trimethylsilylether, 4-benzenesulfonyloxy-α-(t-butyl)benzylalcohol trimethylsilylether,

[0135] 4-(p-toluenesulfonyloxy)-α-(t-butyl)benzyl acetate,4-methanesulfonyloxy-α-(t-butyl)benzyl acetate,4-benzenesulfonyloxy-α-(t-butyl)benzyl acetate,

[0136] 4-(p-toluenesulfonyloxy)-α-ethyl-α-methylbenzylalcohol,4-methanesulfonyloxy-α-ethyl-α-methylbenzylalcohol,4-benzenesulfonyloxy-α-ethyl-α-methylbenzylalcohol,4-(p-toluenesulfonyloxy)-α-ethyl-α-methylbenzylalcohol methyl ether,4-methanesulfonyloxy-α-ethyl-α-methylbenzylalcohol methyl ether,4-benzenesulfonyloxy-α-ethyl-α-methylbenzylalcohol methyl ether,

[0137] 4-(p-toluenesulfonyloxy)-α-ethyl-α-methylbenzylalcohol benzylether, 4-methanesulfonyloxy-α-ethyl-α-methylbenzylalcohol benzyl ether,4-benzenesulfonyloxy-α-ethyl-α-methylbenzylalcohol benzyl ether,

[0138] 4-(p-toluenesulfonyloxy)-α-ethyl-α-methylbenzylalcoholtrimethylsilyl ether, 4-methanesulfonyloxy-α-ethyl-α-methylbenzylalcoholtrimethylsilyl ether, 4-benzenesulfonyloxy-α-ethyl-α-methylbenzylalcoholtrimethylsilyl ether,

[0139] 4-(p-toluenesulfonyloxy)-α-ethyl-α-methylbenzyl acetate,4-methanesulfonyloxy-α-ethyl-α-methylbenzyl acetate,4-benzenesulfonyloxy-α-ethyl-α-methylbenzyl acetate,4-(p-toluenesulfonyloxy)-α-cyanobenzylalcohol,4-methanesulfonyloxy-α-cyanobenzylalcohol,4-benzenesulfonyloxy-α-cyanobenzylalcohol,

[0140] 4-(p-toluenesulfonyloxy)-α-cyanobenzylalcohol methyl ether,4-methanesulfonyloxy-α-cyanobenzylalcohol methyl ether,4-benzenesulfonyloxy-α-cyanobenzylalcohol methyl ether,4-(p-toluenesulfonyloxy)-α-cyanobenzylalcohol benzyl ether,4-methanesulfonyloxy-α-cyanobenzylalcohol benzyl ether,4-benzenesulfonyloxy-α-cyanobenzylalcohol benzyl ether,4-(p-toluenesulfonyloxy)-α-cyanobenzylalcohol trimethylsilyl ether,4-methanesulfonyloxy-α-cyanobenzylalcohol trimethylsilyl ether,4-benzenesulfonyloxy-α-cyanobenzylalcohol trimethylsilyl ether,

[0141] 4-(p-toluenesulfonyloxy)-α-cyanobenzyl acetate,4-methanesulfonyloxy-α-cyanobenzyl acetate,4-benzenesulfonyloxy-α-cyanobenzyl acetate,3-(p-toluenesulfonyloxy)-α-cyanobenzylalcohol,3-methanesulfonyloxy-α-cyanobenzylalcohol,3-benzenesulfonyloxy-α-cyanobenzylalcohol,3-(p-toluenesulfonyloxy)-α-cyanobenzylalcohol methyl ether,3-methanesulfonyloxy-α-cyanobenzylalcohol methyl ether,3-benzenesulfonyloxy-α-cyanobenzylalcohol methyl ether,

[0142] 3-(p-toluenesulfonyloxy)-α-cyanobenzylalcohol benzyl ether,3-methanesulfonyloxy-α-cyanobenzylalcohol benzyl ether,3-benzenesulfonyloxy-α-cyanobenzylalcohol benzyl ether,

[0143] 3-(p-toluenesulfonyloxy)-α-cyanobenzylalcohol trimethylsilylether, 3-methanesulfonyloxy-α-cyanobenzylalcohol trimethylsilyl ether,3-benzenesulfonyloxy-α-cyanobenzylalcohol trimethylsilyl ether,

[0144] 3-(p-toluenesulfonyloxy)-α-cyanobenzyl acetate,3-methanesulfonyloxy-α-cyanobenzyl acetate,3-benzenesulfonyloxy-α-cyanobenzyl acetate,2-(p-toluenesulfonyloxy)-α-cyanobenzylalcohol,2-methanesulfonyloxy-α-cyanobenzylalcohol,2-benzenesulfonyloxy-α-cyanobenzylalcohol,

[0145] 2-(p-toluenesulfonyloxy)-α-cyanobenzylalcohol methyl ether,2-methanesulfonyloxy-α-cyanobenzylalcohol methyl ether,2-benzenesulfonyloxy-α-cyanobenzylalcohol methyl ether,

[0146] 2-(p-toluenesulfonyloxy)-α-cyanobenzylalcohol benzyl ether,2-methanesulfonyloxy-α-cyanobenzylalcohol benzyl ether,2-benzenesulfonyloxy-α-cyanobenzylalcohol benzyl ether,

[0147] 2-(p-toluenesulfonyloxy)-α-cyanobenzylalcohol trimethylsilylether, 2-methanesulfonyloxy-α-cyanobenzylalcohol trimethylsilyl ether,2-benzenesulfonyloxy-α-cyanobenzylalcohol trimethylsilyl ether,

[0148] 2-(p-toluenesulfonyloxy)-α-cyanobenzyl acetate,2-methanesulfonyloxy-α-cyanobenzyl acetate,2-benzenesulfonyloxy-α-cyanobenzyl acetate,

[0149] 1-hydroxy-1-(4-(p-toluenesulfonyloxy)phenyl)propanone,1-methoxy-1-(4-(p-toluenesulfonyloxy)phenyl)propanone,1-benzyloxy-1-(4-(p-toluenesulfonyloxy)phenyl)propanone,

[0150] 1-acetyloxy-1-(4-(p-toluenesulfonyloxy)phenyl)propanone,1-trimethylsilyloxy-1-(4-(p-toluenesulfonyloxy)phenyl)propanone,1-hydroxy-1-(3-(p-toluenesulfonyloxy)phenyl)propanone,

[0151] 1-methoxy-1-(3-(p-toluenesulfonyloxy)phenyl)propanone,1-benzyloxy-1-(3-(p-toluenesulfonyloxy)phenyl)propanone,1-acetyloxy-1-(3-(p-toluenesulfonyloxy)phenyl)propanone,1-trimethylsilyloxy-1-(3-(p-toluenesulfonyloxy)phenyl)propanone,1-hydroxy-1-(2-(p-toluenesulfonyloxy)phenyl)propanone,1-methoxy-1-(2-(p-toluenesulfonyloxy)phenyl)propanone,1-benzyloxy-1-(2-(p-toluenesulfonyloxy)phenyl)propanone,1-acetyloxy-1-(2-(p-toluenesulfonyloxy)phenyl)propanone,1-trimethylsilyloxy-1-(2-(p-toluenesulfonyloxy)phenyl)propanone,1-hydroxy-1-(4-methanesulfonyloxyphenyl)propanone,1-methoxy-1-(4-methanesulfonyloxyphenyl)propanone,1-benzyloxy-1-(4-methanesulfonyloxyphenyl)propanone,1-acetyloxy-1-(4-methanesulfonyloxyphenyl)propanone,1-trimethylsilyloxy-1-(4-methanesulfonyloxyphenyl)propanone,1-hydroxy-1-(3-methanesulfonyloxyphenyl)propanone,1-methoxy-1-(3-methanesulfonyloxyphenyl)propanone,1-benzyloxy-1-(3-methanesulfonyloxyphenyl)propanone,1-acetyloxy-1-(3-methanesulfonyloxyphenyl)propanone,1-trimethylsilyloxy-1-(3-methanesulfonyloxyphenyl)propanone,1-hydroxy-1-(2-methanesulfonyloxyphenyl)propanone,1-methoxy-1-(2-methanesulfonyloxyphenyl)propanone,1-benzyloxy-1-(2-methanesulfonyloxyphenyl)propanone,1-acetyloxy-1-(2-methanesulfonyloxyphenyl)propanone,1-trimethylsilyloxy-1-(2-methanesulfonyloxyphenyl)propanone,1-hydroxy-1-(4-benzenesulfonyloxyphenyl)propanone,1-methoxy-1-(4-benzenesulfonyloxyphenyl)propanone,1-benzyloxy-1-(4-benzenesulfonyloxyphenyl)propanone,1-acetyloxy-1-(4-benzenesulfonyloxyphenyl)propanone,1-trimethylsilyloxy-1-(4-benzenesulfonyloxyphenyl)propanone,1-hydroxy-1-(3-benzenesulfonyloxyphenyl)propanone,1-methoxy-1-(3-benzenesulfonyloxyphenyl)propanone,1-benzyloxy-1-(3-benzenesulfonyloxyphenyl)propanone,1-acetyloxy-1-(3-benzenesulfonyloxyphenyl)propanone,1-trimethylsilyloxy-1-(3-benzenesulfonyloxyphenyl)propanone,1-hydroxy-1-(2-benzenesulfonyloxyphenyl)propanone,1-methoxy-1-(2-benzenesulfonyloxyphenyl)propanone,1-benzyloxy-1-(2-benzenesulfonyloxyphenyl)propanone,1-acetyloxy-1-(2-benzenesulfonyloxyphenyl)propanone,1-trimethylsilyloxy-1-(2-benzenesulfonyloxyphenyl)propanone

[0152] 2-hydroxy-2-(4-(p-toluenesulfonyloxy)phenyl)acetic acid methylester, 2-methoxy-2-(4-(p-toluenesulfonyloxy)phenyl)acetic acid methylester, 2-benzyloxy-2-(4-(p-toluenesulfonyloxy)phenyl)acetic acid methylester, 2-acetyloxy-2-(4-(p-toluenesulfonyloxy)phenyl)acetic acid methylester, 2-trimethylsilyloxy-2-(4-(p-toluenesulfonyloxy)phenyl)acetic acidmethyl ester, 2-hydroxy-2-(3-(p-toluenesulfonyloxy)phenyl)acetic acidmethyl ester, 2-methoxy-2-(3-(p-toluenesulfonyloxy)phenyl)acetic acidmethyl ester, 2-benzyloxy-2-(3-(p-toluenesulfonyloxy)phenyl)acetic acidmethyl ester, 2-acetyloxy-2-(3-(p-toluenesulfonyloxy)phenyl)acetic acidmethyl ester,2-trimethylsilyloxy-2-(3-(p-toluenesulfonyloxy)phenyl)acetic acid methylester, 2-hydroxy-2-(2-(p-toluenesulfonyloxy)phenyl)acetic acid methylester, 2-methoxy-2-(2-(p-toluenesulfonyloxy)phenyl)acetic acid methylester, 2-benzyloxy-2-(2-(p-toluenesulfonyloxy)phenyl)acetic acid methylester, 2-acetyloxy-2-(2-(p-toluenesulfonyloxy)phenyl)acetic acid methylester, 2-trimethylsilyloxy-2-(2-(p-toluenesulfonyloxy)phenyl)acetic acidmethyl ester, 2-hydroxy-2-(4-methanesulfonyloxyphenyl)acetic acid methylester, 2-methoxy-2-(4-methanesulfonyloxyphenyl)acetic acid methyl ester,2-benzyloxy-2-(4-methanesulfonyloxyphenyl)acetic acid methyl ester,2-acetyloxy-2-(4-methanesulfonyloxyphenyl)acetic acid methyl ester,2-trimethylsilyloxy-2-(4-methanesulfonyloxyphenyl)acetic acid methylester, 2-hydroxy-2-(3-methanesulfonyloxyphenyl)acetic acid methyl ester,2-methoxy-2-(3-methanesulfonyloxyphenyl)acetic acid methyl ester,2-benzyloxy-2-(3-methanesulfonyloxyphenyl)acetic acid methyl ester,2-acetyloxy-2-(3-methanesulfonyloxyphenyl)acetic acid methyl ester,2-trimethylsilyloxy-2-(3-methanesulfonyloxyphenyl)acetic acid methylester, 2-hydroxy-2-(2-methanesulfonyloxyphenyl)acetic acid methyl ester,2-methoxy-2-(2-methanesulfonyloxyphenyl)acetic acid methyl ester,2-benzyloxy-2-(2-methanesulfonyloxyphenyl)acetic acid methyl ester,2-acetyloxy-2-(2-methanesulfonyloxyphenyl)acetic acid methyl ester,2-trimethylsilyloxy-2-(2-methanesulfonyloxyphenyl)acetic acid methylester, 2-hydroxy-2-(4-benzenesulfonyloxyphenyl)acetic acid methyl ester,2-methoxy-2-(4-benzenesulfonyloxyphenyl)acetic acid methyl ester,2-benzyloxy-2-(4-benzenesulfonyloxyphenyl)acetic acid methyl ester,2-acetyloxy-2-(4-benzenesulfonyloxyphenyl)acetic acid methyl ester,2-trimethylsilyloxy-2-(4-benzenesulfonyloxyphenyl)acetic acid methylester, 2-hydroxy-2-(3-benzenesulfonyloxyphenyl)acetic acid methyl ester,2-methoxy-2-(3-benzenesulfonyloxyphenyl)acetic acid methyl ester,2-benzyloxy-2-(3-benzenesulfonyloxyphenyl)acetic acid methyl ester,2-acetyloxy-2-(3-benzenesulfonyloxyphenyl)acetic acid methyl ester,2-trimethylsilyloxy-2-(3-benzenesulfonyloxyphenyl)acetic acid methylester, 2-hydroxy-2-(2-benzenesulfonyloxyphenyl)acetic acid methyl ester,2-methoxy-2-(2-benzenesulfonyloxyphenyl)acetic acid methyl ester,2-benzyloxy-2-(2-benzenesulfonyloxyphenyl)acetic acid methyl ester,2-acetyloxy-2-(2-benzenesulfonyloxyphenyl)acetic acid methyl ester,2-trimethylsilyloxy-2-(2-benzenesulfonyloxyphenyl)acetic acid methylester,

[0153] <Formyl, Alcohol>

[0154] 2-hydroxy-2-(4-(p-toluenesulfonyloxy)phenyl)acetaldehyde,

[0155] 2-methoxy-2-(4-(p-toluenesulfonyloxy)phenyl)acetaldehyde,

[0156] 2-benzyloxy-2-(4-(p-toluenesulfonyloxy)phenyl)acetaldehyde,

[0157] 2-acetyloxy-2-(4-(p-toluenesulfonyloxy)phenyl)acetaldehyde,2-trimethylsilyloxy-2-(4-(p-toluenesulfonyloxy)phenyl)acetaldehyde,2-hydroxy-2-(4-methanesulfonyloxyphenyl)acetaldehyde,2-methoxy-2-(4-methanesulfonyloxyphenyl)acetaldehyde,2-benzyloxy-2-(4-methanesulfonyloxyphenyl)acetaldehyde,2-acetyloxy-2-(4-methanesulfonyloxyphenyl)acetaldehyde,2-trimethylsilyloxy-2-(4-methanesulfonyloxyphenyl)acetaldehyde,2-hydroxy-2-(4-benzenesulfonyloxyphenyl)acetaldehyde,2-methoxy-2-(4-benzenesulfonyloxyphenyl)acetaldehyde,2-benzyloxy-2-(4-benzenesulfonyloxyphenyl)acetaldehyde,2-acetyloxy-2-(4-benzenesulfonyloxyphenyl)acetaldehyde,2-trimethylsilyloxy-2-(4-benzenesulfonyloxyphenyl)acetaldehyde,

[0158] 2-hydroxy-2-(4-(p-toluenesulfonyloxy)phenyl)acetamide,2-methoxy-2-(4-(p-toluenesulfonyloxy)phenyl)acetamide,2-benzyloxy-2-(4-(p-toluenesulfonyloxy)phenyl)acetamide,2-acetyloxy-2-(4-(p-toluenesulfonyloxy)phenyl)acetamide,2-trimethylsilyloxy-2-(4-(p-toluenesulfonyloxy)phenyl)acetamide,2-hydroxy-2-(4-methanesulfonyloxyphenyl)acetamide,2-methoxy-2-(4-methanesulfonyloxyphenyl)acetamide,2-benzyloxy-2-(4-methanesulfonyloxyphenyl)acetamide,2-acetyloxy-2-(4-methanesulfonyloxyphenyl)acetamide,2-trimethylsilyloxy-2-(4-methanesulfonyloxyphenyl)acetamide,2-hydroxy-2-(4-benzenesulfonyloxyphenyl)acetamide,2-methoxy-2-(4-benzenesulfonyloxyphenyl)acetamide,2-benzyloxy-2-(4-benzenesulfonyloxyphenyl)acetamide,2-acetyloxy-2-(4-benzenesulfonyloxyphenyl)acetamide,2-trimethylsilyloxy-2-(4-benzenesulfonyloxyphenyl)acetamide,

[0159]N-(t-butyloxycarbonyl)-1-amino-1-(4-(p-toluenesulfonyloxy)phenyl)ethane,N-benzyloxycarbonyl-1-amino-1-(4-(p-toluenesulfonyloxy)phenyl)ethane,N-(9-fluorenylmethyloxycarbonyl)-1-amino-1-(4-(p-toluenesulfonyloxy)phenyl)ethane,N-acetyl-1-amino-1-(4-(p-toluenesulfonyloxy)phenyl)ethane,N-benzoyl-1-amino-1-(4-(p-toluenesulfonyloxy)phenyl)ethane,N-benzyl-1-amino-1-(4-(p-toluenesulfonyloxy)phenyl)ethane,N,N-dimethyl-1-amino-1-(4-(p-toluenesulfonyloxy)phenyl)ethane,

[0160]N-(t-butyloxycarbonyl)-1-amino-1-(3-(p-toluenesulfonyloxy)phenyl)ethane,N-benzyloxycarbonyl-1-amino-1-(3-(p-toluenesulfonyloxy)phenyl)ethane,N-(9-fluorenylmethyloxycarbonyl)-1-amino-1-(3-(p-toluenesulfonyloxy)phenyl)ethane,N-acetyl-1-amino-1-(3-(p-toluenesulfonyloxy)phenyl)ethane,N-benzoyl-1-amino-1-(3-(p-toluenesulfonyloxy)phenyl)ethane,N-benzyl-1-amino-1-(3-(p-toluenesulfonyloxy)phenyl)ethane,N,N-dimethyl-1-amino-1-(3-(p-toluenesulfonyloxy)phenyl)ethane,

[0161]N-(t-butyloxycarbonyl)-1-amino-1-(2-(p-toluenesulfonyloxy)phenyl)ethane,N-benzyloxycarbonyl-1-amino-1-(2-(p-toluenesulfonyloxy)phenyl)ethane,N-(9-fluorenylmethyloxycarbonyl)-1-amino-1-(2-(p-toluenesulfonyloxy)phenyl)ethane,N-acetyl-1-amino-1-(2-(p-toluenesulfonyloxy)phenyl)ethane,N-benzoyl-1-amino-1-(2-(p-toluenesulfonyloxy)phenyl)ethane,N-benzyl-1-amino-1-(2-(p-toluenesulfonyloxy)phenyl)ethane,N,N-dimethyl-1-amino-1-(2-(p-toluenesulfonyloxy)phenyl)ethane,

[0162]N-(t-butyloxycarbonyl)-1-amino-1-(4-(p-toluenesulfonyloxy)phenyl)propane,N-benzyloxycarbonyl-1-amino-1-(4-(p-toluenesulfonyloxy)phenyl)propane,N-(9-fluorenylmethyloxycarbonyl)-1-amino-1-(4-(p-toluenesulfonyloxy)phenyl)propane,N-acetyl-1-amino-1-(4-(p-toluenesulfonyloxy)phenyl)propane,N-benzoyl-1-amino-1-(4-(p-toluenesulfonyloxy)phenyl)propane,N-benzyl-1-amino-1-(4-(p-toluenesulfonyloxy)phenyl)propane,N,N-dimethyl-1-amino-1-(4-(p-toluenesulfonyloxy)phenyl)propane,

[0163]N-(t-butyloxycarbonyl)-1-amino-1-(2-(p-toluenesulfonyloxy)phenyl)propane,N-benzyloxycarbonyl-1-amino-1-(2-(p-toluenesulfonyloxy)phenyl)propane,N-(9-fluorenylmethyloxycarbonyl)-1-amino-1-(2-(p-toluenesulfonyloxy)phenyl)propane,N-acetyl-1-amino-1-(2-(p-toluenesulfonyloxy)phenyl)propane,N-benzoyl-1-amino-1-(2-(p-toluenesulfonyloxy)phenyl)propane,N-benzyl-1-amino-1-(2-(p-toluenesulfonyloxy)phenyl)propane,N,N-dimethyl-1-amino-1-(2-(p-toluenesulfonyloxy)phenyl)propane,N-(t-butyloxycarbonyl)-2-amino-1-(4-(p-toluenesulfonyloxy)phenyl)propane,N-benzyloxycarbonyl-2-amino-1-(4-(p-toluenesulfonyloxy)phenyl)propane,N-(9-fluorenylmethyloxycarbonyl)-2-amino-1-(4-(p-toluenesulfonyloxy)phenyl)propane,N-acetyl-2-amino-1-(4-(p-toluenesulfonyloxy)phenyl)propane,N-benzoyl-2-amino-1-(4-(p-toluenesulfonyloxy)phenyl)propane,N-benzyl-2-amino-1-(4-(p-toluenesulfonyloxy)phenyl)propane,N,N-dimethyl-2-amino-1-(4-(p-toluenesulfonyloxy)phenyl)propane,

[0164]N-(t-butyloxycarbonyl)-2-amino-1-(3-(p-toluenesulfonyloxy)phenyl)propane,N-benzyloxycarbonyl-2-amino-1-(3-(p-toluenesulfonyloxy)phenyl)propane,N-(9-fluorenylmethyloxycarbonyl)-2-amino-1-(3-(p-toluenesulfonyloxy)phenyl)propane,N-acetyl-2-amino-1-(3-(p-toluenesulfonyloxy)phenyl)propane,N-benzoyl-2-amino-1-(3-(p-toluenesulfonyloxy)phenyl)propane,N-benzyl-2-amino-1-(3-(p-toluenesulfonyloxy)phenyl)propane,N,N-dimethyl-2-amino-1-(3-(p-toluenesulfonyloxy)phenyl)propane,N-(t-butyloxycarbonyl)-2-amino-1-(2-(p-toluenesulfonyloxy)phenyl)propane,N-benzyloxycarbonyl-2-amino-1-(4-(p-toluenesulfonyloxy)phenyl)propane,N-(9-fluorenylmethyloxycarbonyl)-2-amino-1-(2-(p-toluenesulfonyloxy)phenyl)propane,N-acetyl-2-amino-1-(2-(p-toluenesulfonyloxy)phenyl)propane,N-benzoyl-2-amino-1-(2-(p-toluenesulfonyloxy)phenyl)propane,N-benzyl-2-amino-1-(2-(p-toluenesulfonyloxy)phenyl)propane,N,N-dimethyl-2-amino-1-(2-(p-toluenesulfonyloxy)phenyl)propane,N-(t-butyloxycarbonyl)-2-amino-1-(4-(p-toluenesulfonyloxy)phenyl)butane,N-benzyloxycarbonyl-2-amino-1-(4-(p-toluenesulfonyloxy)phenyl)butane,N-(9-fluorenylmethyloxycarbonyl)-2-amino-1-(4-(p-toluenesulfonyloxy)phenyl)butane,N-acetyl-2-amino-1-(4-(p-toluenesulfonyloxy)phenyl)butane,N-benzoyl-2-amino-1-(4-(p-toluenesulfonyloxy)phenyl)butane,N-benzyl-2-amino-1-(4-(p-toluenesulfonyloxy)phenyl)butane,N,N-dimethyl-2-amino-1-(4-(p-toluenesulfonyloxy)phenyl)butane,N-(t-butyloxycarbonyl)-2-amino-1-(3-(p-toluenesulfonyloxy)phenyl)butane,N-benzyloxycarbonyl-2-amino-1-(3-(p-toluenesulfonyloxy)phenyl)butane,N-(9-fluorenylmethyloxycarbonyl)-2-amino-1-(3-(p-toluenesulfonyloxy)phenyl)butane,N-acetyl-2-amino-1-(3-(p-toluenesulfonyloxy)phenyl)butane,N-benzoyl-2-amino-1-(3-(p-toluenesulfonyloxy)phenyl)butane,N-benzyl-2-amino-1-(3-(p-toluenesulfonyloxy)phenyl)butane,N,N-dimethyl-2-amino-1-(3-(p-toluenesulfonyloxy)phenyl)butane,

[0165] <amino, alcohol>

[0166]N-(t-butyloxycarbonyl)-4-(p-toluenesulfonyloxy)-α-aminobenzylalcohol,N-(t-butyloxycarbonyl)-4-methanesulfonyloxy-α-aminobenzylalcohol,N-(t-butyloxycarbonyl)-4-benzenesulfonyloxy-α-aminobenzylalcohol,N-(t-butyloxycarbonyl)-4-(p-toluenesulfonyloxy)-α-aminobenzylalcoholmethyl ether,N-(t-butyloxycarbonyl)-4-methanesulfonyloxy-α-aminobenzylalcohol methylether, N-(t-butyloxycarbonyl)-4-benzenesulfonyloxy-α-aminobenzylalcoholmethyl ether,

[0167]N-(t-butyloxycarbonyl)-4-(p-toluenesulfonyloxy)-α-aminobenzylalcoholbenzyl ether,N-(t-butyloxycarbonyl)-4-methanesulfonyloxy-α-aminobenzylalcohol benzylether, N-(t-butyloxycarbonyl)-4-benzenesulfonyloxy-α-aminobenzylalcoholbenzyl ether,

[0168] N-(t-butyloxycarbonyl)-4-(p-toluenesulfonyloxy)-α-aminobenzylacetate, N-(t-butyloxycarbonyl)-4-methanesulfonyloxy-α-aminobenzylacetate, 4-benzenesulfonyloxy-α-aminobenzyl acetate,

[0169]N-(t-butyloxycarbonyl)-4-(p-toluenesulfonyloxy)-α-aminomethylbenzylalcohol,N-(t-butyloxycarbonyl)-4-methanesulfonyloxy-α-aminomethylbenzylalcohol,N-(t-butyloxycarbonyl)-4-benzenesulfonyloxy-α-aminomethylbenzylalcohol,

[0170]N-(t-butyloxycarbonyl)-4-(p-toluenesulfonyloxy)-α-aminomethylbenzylalcoholmethyl ether,N-(t-butyloxycarbonyl)-4-methanesulfonyloxy-α-aminomethylbenzylalcoholmethyl ether,N-(t-butyloxycarbonyl)-4-benzenesulfonyloxy-α-aminomethylbenzylalcoholmethyl ether,

[0171]N-(t-butyloxycarbonyl)-4-(p-toluenesulfonyloxy)-α-aminomethylbenzylalcoholbenzyl ether,N-(t-butyloxycarbonyl)-4-methanesulfonyloxy-α-aminomethylbenzylalcoholbenzyl ether,N-(t-butyloxycarbonyl)-4-benzenesulfonyloxy-α-aminomethylbenzylalcoholbenzyl ether,

[0172]N-(t-butyloxycarbonyl)-4-(p-toluenesulfonyloxy)-α-aminomethylbenzylacetate, N-(t-butyloxycarbonyl)-4-methanesulfonyloxy-α-aminomethylbenzylacetate, 4-benzenesulfonyloxy-α-aminomethylbenzyl acetate,

[0173]N-(t-butyloxycarbonyl)-3-(p-toluenesulfonyloxy)-α-aminomethylbenzylalcohol,N-(t-butyloxycarbonyl)-3-methanesulfonyloxy-α-aminomethylbenzylalcohol,N-(t-butyloxycarbonyl)-3-benzenesulfonyloxy-α-aminomethylbenzylalcohol,

[0174]N-(t-butyloxycarbonyl)-3-(p-toluenesulfonyloxy)-α-aminomethylbenzylalcoholmethyl ether,N-(t-butyloxycarbonyl)-3-methanesulfonyloxy-α-aminomethylbenzylalcoholmethyl ether,N-(t-butyloxycarbonyl)-3-benzenesulfonyloxy-α-aminomethylbenzylalcoholmethyl ether,

[0175]N-(t-butyloxycarbonyl)-3-(p-toluenesulfonyloxy)-α-aminomethylbenzylalcoholbenzyl ether,N-(t-butyloxycarbonyl)-3-methanesulfonyloxy-α-aminomethylbenzylalcoholbenzyl ether,N-(t-butyloxycarbonyl)-3-benzenesulfonyloxy-α-aminomethylbenzylalcoholbenzyl ether,

[0176]N-(t-butyloxycarbonyl)-3-(p-toluenesulfonyloxy)-α-aminomethylbenzylacetate, N-(t-butyloxycarbonyl)-3-methanesulfonyloxy-α-aminomethylbenzylacetate 3-benzenesulfonyloxy-α-aminomethylbenzyl acetate,

[0177]N-(t-butyloxycarbonyl)-2-(p-toluenesulfonyloxy)-αaminomethylbenzylalcohol,N-(t-butyloxycarbonyl)-2-methanesulfonyloxy-α-aminomethylbenzylalcohol,N-(t-butyloxycarbonyl)-2-benzenesulfonyloxy-α-aminomethylbenzylalcohol,

[0178]N-(t-butyloxycarbonyl)-2-(p-toluenesulfonyloxy)-α-aminomethylbenzylalcoholmethyl ether,N-(t-butyloxycarbonyl)-2-methanesulfonyloxy-α-aminomethylbenzylalcoholmethyl ether,N-(t-butyloxycarbonyl)-2-benzenesulfonyloxy-α-aminomethylbenzylalcoholmethyl ether,

[0179]N-(t-butyloxycarbonyl)-2-(p-toluenesulfonyloxy)-α-aminomethylbenzylalcoholbenzyl ether,N-(t-butyloxycarbonyl)-2-methanesulfonyloxy-α-aminomethylbenzylalcoholbenzyl ether,N-(t-butyloxycarbonyl)-2-benzenesulfonyloxy-α-aminomethylbenzylalcoholbenzyl ether,

[0180]N-(t-butyloxycarbonyl)-2-(p-toluenesulfonyloxy)-α-aminomethylbenzylacetate, N-(t-butyloxycarbonyl)-2-methanesulfonyloxy-α-aminomethylbenzylacetate, N-(t-butyloxycarbonyl)-2-benzenesulfonyloxy-α-aminomethylbenzylacetate,

[0181] 1-(2,2-dimethyl-5-oxazolidinyl-3-(p-toluenesulfonyloxy)benzene,

[0182]N-(t-butyloxycarbonyl)-4-(p-toluenesulfonyloxy)-α-methyl-α-aminomethylbenzylalcohol,N-(t-butyloxycarbonyl)-4-methanesulfonyloxy-α-methyl-α-aminomethylbenzylalcohol,N-(t-butyloxycarbonyl)-4-benzenesulfonyloxy-α-methyl-α-aminomethylbenzylalcohol,

[0183]N-(t-butyloxycarbonyl)-4-(p-toluenesulfonyloxy)-α-methyl-α-aminomethylbenzylalcoholmethyl ether,N-(t-butyloxycarbonyl)-4-methanesulfonyloxy-α-methyl-α-aminomethylbenzylalcoholmethyl ether,N-(t-butyloxycarbonyl)-4-benzenesulfonyloxy-α-methyl-α-aminomethylbenzylalcoholmethyl ether,

[0184]N-(t-butyloxycarbonyl)-4-(p-toluenesulfonyloxy)-α-methyl-α-aminomethylbenzylalcoholbenzyl ether,N-(t-butyloxycarbonyl)-4-methanesulfonyloxy-α-methyl-α-aminomethylbenzylalcoholbenzyl ether,N-(t-butyloxycarbonyl)-4-benzenesulfonyloxy-α-methyl-α-aminomethylbenzylalcoholbenzyl ether,

[0185]N-(t-butyloxycarbonyl)-4-(p-toluenesulfonyloxy)-α-methyl-α-aminomethylbenzylacetate,N-(t-butyloxycarbonyl)-4-methanesulfonyloxy-α-methyl-α-aminomethylbenzylacetate,N-(t-butyloxycarbonyl)-4-benzenesulfonyloxy-α-methyl-α-aminomethylbenzylacetate,

[0186]N-(t-butyloxycarbonyl)-3-(p-toluenesulfonyloxy)-α-methyl-α-aminomethylbenzylalcohol,N-(t-butyloxycarbonyl)-3-methanesulfonyloxy-α-methyl-α-aminomethylbenzylalcohol,N-(t-butyloxycarbonyl)-3-benzenesulfonyloxy-α-methyl-α-aminomethylbenzylalcohol,

[0187]N-(t-butyloxycarbonyl)-3-(p-toluenesulfonyloxy)-α-methyl-α-aminomethylbenzylalcoholmethyl ether,N-(t-butyloxycarbonyl)-3-methanesulfonyloxy-α-methyl-αaminomethylbenzylalcoholmethyl ether,N-(t-butyloxycarbonyl)-3-benzenesulfonyloxy-α-methyl-α-aminomethylbenzylalcoholmethyl ether,

[0188]N-(t-butyloxycarbonyl)-3-(p-toluenesulfonyloxy)-α-methyl-α-aminomethylbenzylalcoholbenzyl ether,N-(t-butyloxycarbonyl)-3-methanesulfonyloxy-α-methyl-α-aminomethylbenzylalcoholbenzyl ether,N-(t-butyloxycarbonyl)-3-benzenesulfonyloxy-α-methyl-α-aminomethylbenzylalcoholbenzyl ether,

[0189]N-(t-butyloxycarbonyl)-3-(p-toluenesulfonyloxy)-α-methyl-α-aminomethylbenzylacetate,N-(t-butyloxycarbonyl)-3-methanesulfonyloxy-α-methyl-α-aminomethylbenzylacetate,

[0190]N-(t-butyloxycarbonyl)-3-benzenesulfonyloxy-α-methyl-α-aminomethylbenzylacetate,

[0191]N-(t-butyloxycarbonyl)-1-amino-2-(4-(p-toluenesulfonyloxy)phenyl)ethylalcohol,N-(t-butyloxycarbonyl)-1-amino-2-(4-methanesulfonyloxyphenyl)ethylalcohol,N-(t-butyloxycarbonyl)-1-amino-2-(4-benzenesulfonyloxyphenyl)ethylalcohol,

[0192]N-(t-butyloxycarbonyl)-1-amino-2-(4-(p-toluenesulfonyloxy)phenyl)ethylalcoholmethyl ether,N-(t-butyloxycarbonyl)-1-amino-2-(4-methanesulfonyloxyphenyl)ethylalcoholmethyl ether,N-(t-butyloxycarbonyl)-1-amino-2-(4-benzenesulfonyloxyphenyl)ethylalcoholmethyl ether,N-(t-butyloxycarbonyl)-1-amino-2-(4-(p-toluenesulfonyloxy)phenyl)ethylalcoholbenzyl ether,N-(t-butyloxycarbonyl)-1-amino-2-(4-methanesulfonyloxyphenyl)ethylalcoholbenzyl ether,N-(t-butyloxycarbonyl)-1-amino-2-(4-benzenesulfonyloxyphenyl)ethylalcoholbenzyl ether,

[0193]N-(t-butyloxycarbonyl)-1-amino-2-(4-(p-toluenesulfonyloxy)phenyl)ethylacetate,N-(t-butyloxycarbonyl)-1-amino-2-(4-methanesulfonyloxyphenyl)ethylacetate,N-(t-butyloxycarbonyl)-1-amino-2-(4-benzenesulfonyloxyphenyl)ethylacetate,

[0194]N-(t-butyloxycarbonyl)-2-amino-3-(4-(p-toluenesulfonyloxy)phenyl)propylalcohol,N-(t-butyloxycarbonyl)-2-amino-3-(4-methanesulfonyloxyphenyl)propylalcohol,N-(t-butyloxycarbonyl)-2-amino-3-(4-benzenesulfonyloxyphenyl)propylalcohol,

[0195]N-(t-butyloxycarbonyl)-2-amino-3-(4-(p-toluenesulfonyloxy)phenyl)propylalcoholmethyl ether,N-(t-butyloxycarbonyl)-2-amino-3-(4-methanesulfonyloxyphenyl)propylalcoholmethyl ether,N-(t-butyloxycarbonyl)-2-amino-3-(4-benzenesulfonyloxyphenyl)propylalcoholmethyl ether,

[0196]N-(t-butyloxycarbonyl)-2-amino-3-(4-(p-toluenesulfonyloxy)phenyl)propylalcoholbenzyl ether,N-(t-butyloxycarbonyl)-2-amino-3-(4-methanesulfonyloxyphenyl)propylalcoholbenzyl ether,N-(t-butyloxycarbonyl)-2-amino-3-(4-benzenesulfonyloxyphenyl)propylalcoholbenzyl ether,

[0197]N-(t-butyloxycarbonyl)-2-amino-3-(4-(p-toluenesulfonyloxy)phenyl)propylacetate,N-(t-butyloxycarbonyl)-2-amino-3-(4-methanesulfonyloxyphenyl)propylacetate,N-(t-butyloxycarbonyl)-2-amino-3-(4-benzenesulfonyloxyphenyl)propylacetate,

[0198] N-(t-butyloxycarbonyl)-O-(p-toluenesulfonyl)tyrosine methylester, N-(t-butyloxycarbonyl)-O-(p-toluenesulfonyl)tyrosine ethyl ester,N-(t-butyloxycarbonyl)-O-(p-toluenesulfonyl)tyrosine isopropyl ester,N-(t-butyloxycarbonyl)-O-(p-toluenesulfonyl)tyrosine t-butyl ester,N-(t-butyloxycarbonyl)-O-(p-toluenesulfonyl)tyrosine benzyl ester,

[0199] N-(t-butyloxycarbonyl)-O-methanesulfonyltyrosine methyl ester,N-(t-butyloxycarbonyl)-O-methanesulfonyltyrosine ethyl ester,N-(t-butyloxycarbonyl)-O-methanesulfonyltyrosine isopropyl ester,N-(t-butyloxycarbonyl)-O-methanesulfonyltyrosine t-butyl ester,

[0200] N-(t-butyloxycarbonyl)-O-methanesulfonyltyrosine benzyl ester,

[0201] N-(t-butyloxycarbonyl)-O-benzenesulfonyltyrosine methyl ester,N-(t-butyloxycarbonyl)-O-benzenesulfonyltyrosine ethyl ester,N-(t-butyloxycarbonyl)-O-benzenesulfonyltyrosine isopropyl ester,N-(t-butyloxycarbonyl)-O-benzenesulfonyltyrosine t-butyl ester,

[0202] N-(t-butyloxycarbonyl)-O-benzenesulfonyltyrosine benzyl ester,

[0203] N-acetyl-O-(p-toluenesulfonyl)tyrosine methyl ester,N-acetyl-O-(p-toluenesulfonyl)tyrosine ethyl ester,N-acetyl-O-(p-toluenesulfonyl)tyrosine isopropyl ester,N-acetyl-O-(p-toluenesulfonyl)tyrosine t-butyl ester,N-acetyl-O-(p-toluenesulfonyl)tyrosine benzyl ester,

[0204] N-acetyl-O-methanesulfonyltyrosine methyl ester,N-acetyl-O-methanesulfonyltyrosine ethyl ester,N-acetyl-O-methanesulfonyltyrosine isopropyl ester,N-acetyl-O-methanesulfonyltyrosine t-butyl ester,N-acetyl-O-methanesulfonyltyrosine benzyl ester,

[0205] N-acetyl-O-benzenesulfonyltyrosine methyl ester,N-acetyl-O-benzenesulfonyltyrosine ethyl ester,N-acetyl-O-benzenesulfonyltyrosine isopropyl ester,N-acetyl-O-benzenesulfonyltyrosine t-butyl ester,N-acetyl-O-benzenesulfonyltyrosine benzyl ester,

[0206] N-benzyl-O-(p-toluenesulfonyl)tyrosine methyl ester,N-benzyl-O-(p-toluenesulfonyl)tyrosine ethyl ester,N-benzyl-O-(p-toluenesulfonyl)tyrosine isopropyl ester,N-benzyl-O-(p-toluenesulfonyl)tyrosine t-butyl ester,N-benzyl-O-(p-toluenesulfonyl)tyrosine benzyl ester,

[0207] N-benzyl-O-methanesulfonyltyrosine methyl ester,N-benzyl-O-methanesulfonyltyrosine ethyl ester,N-benzyl-O-methanesulfonyltyrosine isopropyl ester,N-benzyl-O-methanesulfonyltyrosine t-butyl ester,N-benzyl-O-methanesulfonyltyrosine benzyl ester,

[0208] N-benzyl-O-benzenesulfonyltyrosine methyl ester,N-benzyl-O-benzenesulfonyltyrosine ethyl ester,N-benzyl-O-benzenesulfonyltyrosine isopropyl ester,N-benzyl-O-benzenesulfonyltyrosine t-butyl ester,N-benzyl-O-benzenesulfonyltyrosine benzyl ester,

[0209] N-(9-fluorenylmethoxycarbonyl)-O-(p-toluenesulfonyl)tyrosinemethyl ester,N-(9-fluorenylmethoxycarbonyl)-O-(p-toluenesulfonyl)tyrosine ethylester, N-(9-fluorenylmethoxycarbonyl)-O-(p-toluenesulfonyl)tyrosineisopropyl ester,N-(9-fluorenylmethoxycarbonyl)-O-(p-toluenesulfonyl)tyrosine t-butylester, N-(9-fluorenylmethoxycarbonyl)-O-(p-toluenesulfonyl)tyrosinebenzyl ester,

[0210] N-(9-fluorenylmethoxycarbonyl)-O-methanesulfonyltyrosine methylester, N-(9-fluorenylmethoxycarbonyl)-O-methanesulfonyltyrosine ethylester, N-(9-fluorenylmethoxycarbonyl)-O-methanesulfonyltyrosineisopropyl ester,N-(9-fluorenylmethoxycarbonyl)-O-methanesulfonyltyrosine t-butyl ester,N-(9-fluorenylmethoxycarbonyl)-O-methanesulfonyltyrosine benzyl ester,

[0211] N-(9-fluorenylmethoxycarbonyl)-O-benzenesulfonyltyrosine methylester, N-(9-fluorenylmethoxycarbonyl)-O-benzenesulfonyltyrosine ethylester, N-(9-fluorenylmethoxycarbonyl)-O-benzenesulfonyltyrosineisopropyl ester,N-(9-fluorenylmethoxycarbonyl)-O-benzenesulfonyltyrosine t-butyl ester,N-(9-fluorenylmethoxycarbonyl)-O-benzenesulfonyltyrosine benzyl ester,

[0212] N-benzyloxycarbonyl-O-(p-toluenesulfonyl)tyrosine methyl ester,N-benzyloxycarbonyl-O-(p-toluenesulfonyl)tyrosine ethyl ester,N-benzyloxycarbonyl-O-(p-toluenesulfonyl)tyrosine isopropyl ester,N-benzyloxycarbonyl-O-(p-toluenesulfonyl)tyrosine t-butyl ester,N-benzyloxycarbonyl-O-(p-toluenesulfonyl)tyrosine benzyl ester,

[0213] N-benzyloxycarbonyl-O-methanesulfonyltyrosine methyl ester,

[0214] N-benzyloxycarbonyl-O-methanesulfonyltyrosine ethyl ester,

[0215] N-benzyloxycarbonyl-O-methanesulfonyltyrosine isopropyl ester,N-benzyloxycarbonyl-O-methanesulfonyltyrosine t-butyl ester,N-benzyloxycarbonyl-4-mesylphenylglycine benzyl ester,

[0216] N-benzyloxycarbonyl-O-benzenesulfonyltyrosine methyl ester,

[0217] N-benzyloxycarbonyl-O-benzenesulfonyltyrosine ethyl ester,

[0218] N-benzyloxycarbonyl-O-benzenesulfonyltyrosine isopropyl ester,N-benzyloxycarbonyl-O-benzenesulfonyltyrosine t-butyl ester,N-benzyloxycarbonyl-O-benzenesulfonyltyrosine benzyl ester,

[0219] N-(t-butyloxycarbonyl)-O-(p-toluenesulfonyl)-m-tyrosine methylester, N-(t-butyloxycarbonyl)-O-(p-toluenesulfonyl)-m-tyrosine ethylester, N-(t-butyloxycarbonyl)-O-(p-toluenesulfonyl)-m-tyrosine isopropylester, N-(t-butyloxycarbonyl)-O-(p-toluenesulfonyl)-m-tyrosine t-butylester, N-(t-butyloxycarbonyl)-O-(p-toluenesulfonyl)-m-tyrosine benzylester,

[0220] N-(t-butyloxycarbonyl)-O-methanesulfonyl-m-tyrosine methyl ester,N-(t-butyloxycarbonyl)-O-methanesulfonyl-m-tyrosine ethyl ester,N-(t-butyloxycarbonyl)-O-methanesulfonyl-m-tyrosine isopropyl ester,N-(t-butyloxycarbonyl)-O-methanesulfonyl-m-tyrosine t-butyl ester,N-(t-butyloxycarbonyl)-O-methanesulfonyl-m-tyrosine benzyl ester,

[0221] N-(t-butyloxycarbonyl)-O-benzenesulfonyl-m-tyrosine methyl ester,N-(t-butyloxycarbonyl)-O-benzenesulfonyl-m-tyrosine ethyl ester,N-(t-butyloxycarbonyl)-O-benzenesulfonyl-m-tyrosine isopropyl ester,N-(t-butyloxycarbonyl)-O-benzenesulfonyl-m-tyrosine t-butyl ester,N-(t-butyloxycarbonyl)-O-benzenesulfonyl-m-tyrosine benzyl ester,

[0222] N-acetyl-O-(p-toluenesulfonyl)-m-tyrosine methyl ester,N-acetyl-O-(p-toluenesulfonyl)-m-tyrosine ethyl ester,N-acetyl-O-(p-toluenesulfonyl)-m-tyrosine isopropyl ester,N-acetyl-O-(p-toluenesulfonyl)-m-tyrosine t-butyl ester,N-acetyl-O-(p-toluenesulfonyl)-m-tyrosine benzyl ester,N-acetyl-O-methanesulfonyl-m-tyrosine methyl ester,N-acetyl-O-methanesulfonyl-m-tyrosine ethyl ester,N-acetyl-O-methanesulfonyl-m-tyrosine isopropyl ester,N-acetyl-O-methanesulfonyl-m-tyrosine t-butyl ester,N-acetyl-O-methanesulfonyl-m-tyrosine benzyl ester,N-acetyl-O-benzenesulfonyl-m-tyrosine methyl ester,N-acetyl-O-benzenesulfonyl-m-tyrosine ethyl ester,N-acetyl-O-benzenesulfonyl-m-tyrosine isopropyl ester,N-acetyl-O-benzenesulfonyl-m-tyrosine t-butyl ester,N-acetyl-O-benzenesulfonyl-m-tyrosine benzyl ester,

[0223] N-benzyl-O-(p-toluenesulfonyl)-m-tyrosine methyl ester,N-benzyl-O-(p-toluenesulfonyl)-m-tyrosine ethyl ester,N-benzyl-O-(p-toluenesulfonyl)-m-tyrosine isopropyl ester,N-benzyl-O-(p-toluenesulfonyl)-m-tyrosine t-butyl ester,N-benzyl-O-(p-toluenesulfonyl)-m-tyrosine benzyl ester,N-benzyl-O-methanesulfonyl-m-tyrosine methyl ester,N-benzyl-O-methanesulfonyl-m-tyrosine ethyl ester,N-benzyl-O-methanesulfonyl-m-tyrosine isopropyl ester,N-benzyl-O-methanesulfonyl-m-tyrosine t-butyl ester,N-benzyl-O-methanesulfonyl-m-tyrosine benzyl ester,N-benzyl-O-benzenesulfonyl-m-tyrosine methyl ester,N-benzyl-O-benzenesulfonyl-m-tyrosine ethyl ester,N-benzyl-O-benzenesulfonyl-m-tyrosine isopropyl ester,N-benzyl-O-benzenesulfonyl-m-tyrosine t-butyl ester,N-benzyl-O-benzenesulfonyl-m-tyrosine benzyl ester,

[0224] N-(9-fluorenylmethoxycarbonyl)-O-(p-toluenesulfonyl)-m-tyrosinemethyl ester,N-(9-fluorenylmethoxycarbonyl)-O-(p-toluenesulfonyl)-m-tyrosine ethylester, N-(9-fluorenylmethoxycarbonyl)-O-(p-toluenesulfonyl)-m-tyrosineisopropyl ester,N-(9-fluorenylmethoxycarbonyl)-O-(p-toluenesulfonyl)-m-tyrosine t-butylester, N-(9-fluorenylmethoxycarbonyl)-O-(p-toluenesulfonyl)-m-tyrosinebenzyl ester,N-(9-fluorenylmethoxycarbonyl)-O-methanesulfonyl-m-tyrosine methylester, N-(9-fluorenylmethoxycarbonyl)-O-methanesulfonyl-m-tyrosine ethylester, N-(9-fluorenylmethoxycarbonyl)-O-methanesulfonyl-m-tyrosineisopropyl ester,N-(9-fluorenylmethoxycarbonyl)-O-methanesulfonyl-m-tyrosine t-butylester, N-(9-fluorenylmethoxycarbonyl)-O-methanesulfonyl-m-tyrosinebenzyl ester,N-(9-fluorenylmethoxycarbonyl)-O-benzenesulfonyl-m-tyrosine methylester, N-(9-fluorenylmethoxycarbonyl)-O-benzenesulfonyl-m-tyrosine ethylester, N-(9-fluorenylmethoxycarbonyl)-O-benzenesulfonyl-m-tyrosineisopropyl ester,N-(9-fluorenylmethoxycarbonyl)-O-benzenesulfonyl-m-tyrosine t-butylester, N-(9-fluorenylmethoxycarbonyl)-O-benzenesulfonyl-m-tyrosinebenzyl ester,

[0225] N-benzyloxycarbonyl-O-(p-toluenesulfonyl)-m-tyrosine methylester, N-benzyloxycarbonyl-O-(p-toluenesulfonyl)-m-tyrosine ethyl ester,N-benzyloxycarbonyl-o-(p-toluenesulfonyl)-m-tyrosine isopropyl ester,N-benzyloxycarbonyl-O-(p-toluenesulfonyl)-m-tyrosine t-butyl ester,N-benzyloxycarbonyl-O-(p-toluenesulfonyl)-m-tyrosine benzyl ester,N-benzyloxycarbonyl-O-methanesulfonyl-m-tyrosine methyl ester,N-benzyloxycarbonyl-O-methanesulfonyl-m-tyrosine ethyl ester,N-benzyloxycarbonyl-O-methanesulfonyl-m-tyrosine isopropyl ester,N-benzyloxycarbonyl-O-methanesulfonyl-m-tyrosine t-butyl ester,N-benzyloxycarbonyl-4-mesylphenylglycine benzyl ester,N-benzyloxycarbonyl-O-benzenesulfonyl-m-tyrosine methyl ester,N-benzyloxycarbonyl-O-benzenesulfonyl-m-tyrosine ethyl ester,N-benzyloxycarbonyl-O-benzenesulfonyl-m-tyrosine isopropyl ester,N-benzyloxycarbonyl-O-benzenesulfonyl-m-tyrosine t-butyl ester,N-benzyloxycarbonyl-O-benzenesulfonyl-m-tyrosine benzyl ester,

[0226] N-(t-butyloxycarbonyl)-O-(p-toluenesulfonyl)-o-tyrosine methylester, N-(t-butyloxycarbonyl)-O-(p-toluenesulfonyl)-O-tyrosine ethylester, N-(t-butyloxycarbonyl)-O-(p-toluenesulfonyl)-O-tyrosine isopropylester, N-(t-butyloxycarbonyl)-O-(p-toluenesulfonyl)-O-tyrosine t-butylester, N-(t-butyloxycarbonyl)-O-(p-toluenesulfonyl)-O-tyrosine benzylester, N-(t-butyloxycarbonyl)-O-methanesulfonyl-O-tyrosine methyl ester,N-(t-butyloxycarbonyl)-O-methanesulfonyl-O-tyrosine ethyl ester,

[0227] N-(t-butyloxycarbonyl)-O-methanesulfonyl-O-tyrosine isopropylester, N-(t-butyloxycarbonyl)-O-methanesulfonyl-O-tyrosine t-butylester, N-(t-butyloxycarbonyl)-O-methanesulfonyl-O-tyrosine benzyl ester,N-(t-butyloxycarbonyl)-O-benzenesulfonyl-O-tyrosine methyl ester,

[0228] N-(t-butyloxycarbonyl)-O-benzenesulfonyl-O-tyrosine ethyl ester,N-(t-butyloxycarbonyl)-O-benzenesulfonyl-O-tyrosine isopropyl ester,N-(t-butyloxycarbonyl)-O-benzenesulfonyl-O-tyrosine t-butyl ester,N-(t-butyloxycarbonyl)-O-benzenesulfonyl-O-tyrosine benzyl ester,

[0229] N-acetyl-O-(p-toluenesulfonyl)-O-tyrosine methyl ester,N-acetyl-O-(p-toluenesulfonyl)-O-tyrosine ethyl ester,N-acetyl-O-(p-toluenesulfonyl)-O-tyrosine isopropyl ester,N-acetyl-O-(p-toluenesulfonyl)-O-tyrosine t-butyl ester,N-acetyl-O-(p-toluenesulfonyl)-O-tyrosine benzyl ester,N-acetyl-O-methanesulfonyl-O-tyrosine methyl ester,N-acetyl-O-methanesulfonyl-O-tyrosine ethyl ester,N-acetyl-O-methanesulfonyl-O-tyrosine isopropyl ester,N-acetyl-O-methanesulfonyl-O-tyrosine t-butyl ester,N-acetyl-O-methanesulfonyl-O-tyrosine benzyl ester,N-acetyl-O-benzenesulfonyl-O-tyrosine methyl ester,N-acetyl-O-benzenesulfonyl-O-tyrosine ethyl ester,N-acetyl-O-benzenesulfonyl-O-tyrosine isopropyl ester,N-acetyl-O-benzenesulfonyl-O-tyrosine t-butyl ester,N-acetyl-O-benzenesulfonyl-O-tyrosine benzyl ester,

[0230] N-benzyl-O-(p-toluenesulfonyl)-O-tyrosine methyl ester,N-benzyl-O-(p-toluenesulfonyl)-O-tyrosine ethyl ester,N-benzyl-O-(p-toluenesulfonyl)-O-tyrosine isopropyl ester,N-benzyl-O-(p-toluenesulfonyl)-O-tyrosine t-butyl ester,N-benzyl-O-(p-toluenesulfonyl)-O-tyrosine benzyl ester,N-benzyl-O-methanesulfonyl-O-tyrosine methyl ester,N-benzyl-O-methanesulfonyl-O-tyrosine ethyl ester,N-benzyl-O-methanesulfonyl-O-tyrosine isopropyl ester,N-benzyl-O-methanesulfonyl-O-tyrosine t-butyl ester,N-benzyl-O-methanesulfonyl-O-tyrosine benzyl ester,N-benzyl-O-benzenesulfonyl-O-tyrosine methyl ester,N-benzyl-O-benzenesulfonyl-O-tyrosine ethyl ester,N-benzyl-O-benzenesulfonyl-O-tyrosine isopropyl ester,N-benzyl-O-benzenesulfonyl-O-tyrosine t-butyl ester,N-benzyl-O-benzenesulfonyl-O-tyrosine benzyl ester,

[0231] N-(9-fluorenylmethoxycarbonyl)-O-(p-toluenesulfonyl)-O-tyrosinemethyl ester,N-(9-fluorenylmethoxycarbonyl)-O-(p-toluenesulfonyl)-O-tyrosine ethylester, N-(9-fluorenylmethoxycarbonyl)-O-(p-toluenesulfonyl)-O-tyrosineisopropyl ester,N-(9-fluorenylmethoxycarbonyl)-O-(p-toluenesulfonyl)-O-tyrosine t-butylester, N-(9-fluorenylmethoxycarbonyl)-O-(p-toluenesulfonyl)-O-tyrosinebenzyl ester,N-(9-fluorenylmethoxycarbonyl)-O-methanesulfonyl-O-tyrosine methylester, N-(9-fluorenylmethoxycarbonyl)-O-methanesulfonyl-O-tyrosine ethylester, N-(9-fluorenylmethoxycarbonyl)-O-methanesulfonyl-O-tyrosineisopropyl ester,N-(9-fluorenylmethoxycarbonyl)-O-methanesulfonyl-O-tyrosine t-butylester, N-(9-fluorenylmethoxycarbonyl)-O-methanesulfonyl-O-tyrosinebenzyl ester,N-(9-fluorenylmethoxycarbonyl)-O-benzenesulfonyl-O-tyrosine methylester, N-(9-fluorenylmethoxycarbonyl)-O-benzenesulfonyl-O-tyrosine ethylester, N-(9-fluorenylmethoxycarbonyl)-O-benzenesulfonyl-O-tyrosineisopropyl ester,N-(9-fluorenylmethoxycarbonyl)-O-benzenesulfonyl-O-tyrosine t-butylester, N-(9-fluorenylmethoxycarbonyl)-O-benzenesulfonyl-O-tyrosinebenzyl ester,

[0232] N-benzyloxycarbonyl-O-(p-toluenesulfonyl)-O-tyrosine methylester, N-benzyloxycarbonyl-O-(p-toluenesulfonyl)-O-tyrosine ethyl ester,N-benzyloxycarbonyl-O-(p-toluenesulfonyl)-O-tyrosine isopropyl ester,N-benzyloxycarbonyl-O-(p-toluenesulfonyl)-O-tyrosine t-butyl ester,N-benzyloxycarbonyl-O-(p-toluenesulfonyl)-O-tyrosine benzyl ester,N-benzyloxycarbonyl-O-methanesulfonyl-O-tyrosine methyl ester,N-benzyloxycarbonyl-O-methanesulfonyl-O-tyrosine ethyl ester,N-benzyloxycarbonyl-O-methanesulfonyl-O-tyrosine isopropyl ester,N-benzyloxycarbonyl-O-methanesulfonyl-O-tyrosine t-butyl ester,N-benzyloxycarbonyl-4-mesylphenylglycine benzyl ester,N-benzyloxycarbonyl-O-benzenesulfonyl-O-tyrosine methyl ester,N-benzyloxycarbonyl-O-benzenesulfonyl-O-tyrosine ethyl ester,N-benzyloxycarbonyl-O-benzenesulfonyl-O-tyrosine isopropyl ester,N-benzyloxycarbonyl-O-benzenesulfonyl-O-tyrosine t-butyl ester,N-benzyloxycarbonyl-O-benzenesulfonyl-O-tyrosine benzyl ester,

[0233] N-(t-butyloxycarbonyl)-2-(4-(p-toluenesulfonyloxy)phenyl)glycinemethyl ester,N-(t-butyloxycarbonyl)-2-(4-(p-toluenesulfonyloxy)phenyl)glycine ethylester, N-(t-butyloxycarbonyl)-2-(4-(p-toluenesulfonyloxy)phenyl)glycineisopropyl ester,N-(t-butyloxycarbonyl)-2-(4-(p-toluenesulfonyloxy)phenyl)glycine t-butylester, N-(t-butyloxycarbonyl)-2-(4-(p-toluenesulfonyloxy)phenyl)glycinebenzyl ester,N-(t-butyloxycarbonyl)-2-(4-methanesulfonyloxyphenyl)glycine methylester, N-(t-butyloxycarbonyl)-2-(4-methanesulfonyloxyphenyl)glycineethyl ester,N-(t-butyloxycarbonyl)-2-(4-methanesulfonyloxyphenyl)glycine isopropylester, N-(t-butyloxycarbonyl)-2-(4-methanesulfonyloxyphenyl)glycinet-butyl ester,N-(t-butyloxycarbonyl)-2-(4-methanesulfonyloxyphenyl)glycine benzylester, N-(t-butyloxycarbonyl)-2-(4-benzenesulfonyloxyphenyl)glycinemethyl ester,N-(t-butyloxycarbonyl)-2-(4-benzenesulfonyloxyphenyl)glycine ethylester, N-(t-butyloxycarbonyl)-2-(4-benzenesulfonyloxyphenyl)glycineisopropyl ester,N-(t-butyloxycarbonyl)-2-(4-benzenesulfonyloxyphenyl)glycine-t-butylester, N-(t-butyloxycarbonyl)-2-(4-benzenesulfonyloxyphenyl)glycinebenzyl ester, N-acetyl-2-(4-(p-toluenesulfonyloxy)phenyl)glycine methylester, N-acetyl-2-(4-(p-toluenesulfonyloxy)phenyl)glycine ethyl ester,N-2-(4-(p-toluenesulfonyloxy)phenyl)glycine isopropyl ester,N-2-(4-(p-toluenesulfonyloxy)phenyl)glycine t-butyl ester,N-acetyl-2-(4-(p-toluenesulfonyloxy)phenyl)glycine benzyl ester,N-acetyl-2-(4-methanesulfonyloxyphenyl)glycine methyl ester,N-acetyl-2-(4-methanesulfonyloxyphenyl)glycine ethyl ester,N-acetyl-2-(4-methanesulfonyloxyphenyl)glycine isopropyl ester,N-acetyl-2-(4-methanesulfonyloxyphenyl)glycine t-butyl ester,N-acetyl-2-(4-methanesulfonyloxyphenyl)glycine benzyl ester,N-acetyl-2-(4-benzenesulfonyloxyphenyl)glycine methyl ester,N-acetyl-2-(4-benzenesulfonyloxyphenyl)glycine ethyl ester,N-acetyl-2-(4-benzenesulfonyloxyphenyl)glycine isopropyl ester,N-acetyl-2-(4-benzenesulfonyloxyphenyl)glycine t-butyl ester,N-acetyl-2-(4-benzenesulfonyloxyphenyl)glycine benzyl ester,N-benzyl-2-(4-(p-toluenesulfonyloxy)phenyl)glycine methyl ester,N-benzyl-2-(4-(p-toluenesulfonyloxy)phenyl)glycine ethyl ester,N-benzyl-2-(4-(p-toluenesulfonyloxy)phenyl)glycine isopropyl ester,N-benzyl-2-(4-(p-toluenesulfonyloxy)phenyl)glycine t-butyl ester,N-benzyl-2-(4-(p-toluenesulfonyloxy)phenyl)glycine benzyl ester,N-benzyl-2-(4-methanesulfonyloxyphenyl)glycine methyl ester,N-benzyl-2-(4-methanesulfonyloxyphenyl)glycine ethyl ester,N-benzyl-2-(4-methanesulfonyloxyphenyl)glycine isopropyl ester,N-benzyl-2-(4-methanesulfonyloxyphenyl)glycine t-butyl ester,

[0234] N-benzyl-2-(4-methanesulfonyloxyphenyl)glycine benzyl ester,

[0235] N-benzyl-2-(4-benzenesulfonyloxyphenyl)glycine methyl ester,

[0236] N-benzyl-2-(4-benzenesulfonyloxyphenyl)glycine ethyl ester,

[0237] N-benzyl-2-(4-benzenesulfonyloxyphenyl)glycine isopropyl ester,N-benzyl-2-(4-benzenesulfonyloxyphenyl)glycine t-butyl ester,N-benzyl-2-(4-benzenesulfonyloxyphenyl)glycine benzyl ester,

[0238]N-(9-fluorenylmethoxycarbonyl)-2-(4-(p-toluenesulfonyloxy)phenyl)glycinemethyl ester,N-(9-fluorenylmethoxycarbonyl)-2-(4-(p-toluenesulfonyloxy)phenyl)glycineethyl ester,N-(9-fluorenylmethoxycarbonyl)-2-(4-(p-toluenesulfonyloxy)phenyl)glycineisopropyl ester,N-(9-fluorenylmethoxycarbonyl)-2-(4-(p-toluenesulfonyloxy)phenyl)glycinet-butyl ester,N-(9-fluorenylmethoxycarbonyl)-2-(4-(p-toluenesulfonyloxy)phenyl)glycinebenzyl ester,N-(9-fluorenylmethoxycarbonyl)-2-(4-methanesulfonyloxyphenyl)glycinemethyl ester,N-(9-fluorenylmethoxycarbonyl)-2-(4-methanesulfonyloxyphenyl)glycineethyl ester,N-(9-fluorenylmethoxycarbonyl)-2-(4-methanesulfonyloxyphenyl)glycineisopropyl ester,N-(9-fluorenylmethoxycarbonyl)-2-(4-methanesulfonyloxyphenyl)glycinet-butyl ester,N-(9-fluorenylmethoxycarbonyl)-2-(4-methanesulfonyloxyphenyl)glycinebenzyl ester,N-(9-fluorenylmethoxycarbonyl)-2-(4-benzenesulfonyloxyphenyl)glycinemethyl ester,N-(9-fluorenylmethoxycarbonyl)-2-(4-benzenesulfonyloxyphenyl)glycineethyl ester,N-(9-fluorenylmethoxycarbonyl)-2-(4-benzenesulfonyloxyphenyl)glycineisopropyl ester,N-(9-fluorenylmethoxycarbonyl)-2-(4-benzenesulfonyloxyphenyl)glycinet-butyl ester,N-(9-fluorenylmethoxycarbonyl)-2-(4-benzenesulfonyloxyphenyl)glycinebenzyl ester,

[0239] N-benzyloxycarbonyl-2-(4-(p-toluenesulfonyloxy)phenyl)glycinemethyl ester,N-benzyloxycarbonyl-2-(4-(p-toluenesulfonyloxy)phenyl)glycine ethylester, N-benzyloxycarbonyl-2-(4-(p-toluenesulfonyloxy)phenyl)glycineisopropyl ester,N-benzyloxycarbonyl-2-(4-(p-toluenesulfonyloxy)phenyl)glycine t-butylester, N-benzyloxycarbonyl-2-(4-(p-toluenesulfonyloxy)phenyl)glycinebenzyl ester, N-benzyloxycarbonyl-2-(4-methanesulfonyloxyphenyl)glycinemethyl ester, N-benzyloxycarbonyl-2-(4-methanesulfonyloxyphenyl)glycineethyl ester, N-benzyloxycarbonyl-2-(4-methanesulfonyloxyphenyl)glycineisopropyl ester,N-benzyloxycarbonyl-2-(4-methanesulfonyloxyphenyl)glycine t-butyl ester,N-benzyloxycarbonyl-2-(4-methanesulfonyloxyphenyl)glycine benzyl ester,N-benzyloxycarbonyl-2-(4-benzenesulfonyloxyphenyl)glycine methyl ester,N-benzyloxycarbonyl-2-(4-benzenesulfonyloxyphenyl)glycine ethyl ester,N-benzyloxycarbonyl-2-(4-benzenesulfonyloxyphenyl)glycine isopropylester, N-benzyloxycarbonyl-2-(4-benzenesulfonyloxyphenyl)glycine t-butylester, N-benzyloxycarbonyl-2-(4-benzenesulfonyloxyphenyl)glycine benzylester,

[0240]N-(t-butyloxycarbonyl)-3-amino-3-(4-(p-toluenesulfonyloxy)phenyl)propanoicacid methyl ester,N-(t-butyloxycarbonyl)-3-amino-3-(4-(p-toluenesulfonyloxy)phenyl)propanoicacid ethyl ester,N-(t-butyloxycarbonyl)-3-amino-3-(4-(p-toluenesulfonyloxy)phenyl)propanoicacid isopropyl ester,

[0241]N-(t-butyloxycarbonyl)-3-amino-3-(4-(p-toluenesulfonyloxy)phenyl)propanoicacid t-butyl ester,N-(t-butyloxycarbonyl)-3-amino-3-(4-(p-toluenesulfonyloxy)phenyl)propanoicacid benzyl ester,N-(t-butyloxycarbonyl)-3-amino-3-(4-methanesulfonyloxyphenyl)propanoicacid methyl ester,N-(t-butyloxycarbonyl)-3-amino-3-(4-methanesulfonyloxyphenyl)propanoicacid ethyl ester,N-(t-butyloxycarbonyl)-3-amino-3-(4-methanesulfonyloxyphenyl)propanoicacid isopropyl ester,N-(t-butyloxycarbonyl)-3-amino-3-(4-methanesulfonyloxyphenyl)propanoicacid t-butyl ester,N-(t-butyloxycarbonyl)-3-amino-3-(4-methanesulfonyloxyphenyl)propanoicacid benzyl ester,N-(t-butyloxycarbonyl)-3-amino-3-(4-benzenesulfonyloxyphenyl)propanoicacid methyl ester,N-(t-butyloxycarbonyl)-3-amino-3-(4-benzenesulfonyloxyphenyl)propanoicacid ethyl ester,N-(t-butyloxycarbonyl)-3-amino-3-(4-benzenesulfonyloxyphenyl)propanoicacid isopropyl ester,N-(t-butyloxycarbonyl)-3-amino-3-(4-benzenesulfonyloxyphenyl)propanoicacid t-butyl ester,N-(t-butyloxycarbonyl)-3-amino-3-(4-benzenesulfonyloxyphenyl)propanoicacid benzyl ester,

[0242] N-acetyl-3-amino-3-(4-(p-toluenesulfonyloxy)phenyl)propanoic acidmethyl ester,N-acetyl-3-amino-3-(4-(p-toluenesulfonyloxy)phenyl)propanoic acid ethylester, N-3-amino-3-(4-(p-toluenesulfonyloxy)phenyl)propanoic acidisopropyl ester,

[0243] N-3-amino-3-(4-(p-toluenesulfonyloxy)phenyl)propanoic acidt-butyl ester,N-acetyl-3-amino-3-(4-(p-toluenesulfonyloxy)phenyl)propanoic acid benzylester, N-acetyl-3-amino-3-(4-methanesulfonyloxyphenyl)propanoic acidmethyl ester, N-acetyl-3-amino-3-(4-methanesulfonyloxyphenyl)propanoicacid ethyl ester,N-acetyl-3-amino-3-(4-methanesulfonyloxyphenyl)propanoic acid isopropylester, N-acetyl-3-amino-3-(4-methanesulfonyloxyphenyl)propanoic acidt-butyl ester, N-acetyl-3-amino-3-(4-methanesulfonyloxyphenyl)propanoicacid benzyl ester,N-acetyl-3-amino-3-(4-benzenesulfonyloxyphenyl)propanoic acid methylester, N-acetyl-3-amino-3-(4-benzenesulfonyloxyphenyl)propanoic acidethyl ester, N-acetyl-3-amino-3-(4-benzenesulfonyloxyphenyl)propanoicacid isopropyl ester,N-acetyl-3-amino-3-(4-benzenesulfonyloxyphenyl)propanoic acid t-butylester, N-acetyl-3-amino-3-(4-benzenesulfonyloxyphenyl)propanoic acidbenzyl ester,

[0244] N-benzyl-3-amino-3-(4-(p-toluenesulfonyloxy)phenyl)propanoic acidmethyl ester,N-benzyl-3-amino-3-(4-(p-toluenesulfonyloxy)phenyl)propanoic acid ethylester, N-benzyl-3-amino-3-(4-(p-toluenesulfonyloxy)phenyl)propanoic acidisopropyl ester,

[0245] N-benzyl-3-amino-3-(4-(p-toluenesulfonyloxy)phenyl)propanoic acidt-butyl ester,N-benzyl-3-amino-3-(4-(p-toluenesulfonyloxy)phenyl)propanoic acid benzylester, N-benzyl-3-amino-3-(4-methanesulfonyloxyphenyl)propanoic acidmethyl ester, N-benzyl-3-amino-3-(4-methanesulfonyloxyphenyl)propanoicacid ethyl ester,N-benzyl-3-amino-3-(4-methanesulfonyloxyphenyl)propanoic acid isopropylester, N-benzyl-3-amino-3-(4-methanesulfonyloxyphenyl)propanoic acidt-butyl ester, N-benzyl-3-amino-3-(4-methanesulfonyloxyphenyl)propanoicacid benzyl ester,N-benzyl-3-amino-3-(4-benzenesulfonyloxyphenyl)propanoic acid methylester, N-benzyl-3-amino-3-(4-benzenesulfonyloxyphenyl)propanoic acidethyl ester, N-benzyl-3-amino-3-(4-benzenesulfonyloxyphenyl)propanoicacid isopropyl ester,N-benzyl-3-amino-3-(4-benzenesulfonyloxyphenyl)propanoic acid t-butylester, N-benzyl-3-amino-3-(4-benzenesulfonyloxyphenyl)propanoic acidbenzyl ester,

[0246]N-(9-fluorenylmethoxycarbonyl)-3-amino-3-(4-(p-toluenesulfonyloxy)phenyl)propanoicacid methyl ester,N-(9-fluorenylmethoxycarbonyl)-3-amino-3-(4-(p-toluenesulfonyloxy)phenyl)propanoicacid ethyl ester,N-(9-fluorenylmethoxycarbonyl)-3-amino-3-(4-(p-toluenesulfonyloxy)phenyl)propanoicacid isopropyl ester,

[0247]N-(9-fluorenylmethoxycarbonyl)-3-amino-3-(4-(p-toluenesulfonyloxy)phenyl)propanoicacid t-butyl ester,N-(9-fluorenylmethoxycarbonyl)-3-amino-3-(4-(p-toluenesulfonyloxy)phenyl)propanoicacid benzyl ester,N-(9-fluorenylmethoxycarbonyl)-3-amino-3-(4-methanesulfonyloxyphenyl)propanoicacid methyl ester,N-(9-fluorenylmethoxycarbonyl)-3-amino-3-(4-methanesulfonyloxyphenyl)propanoicacid ethyl ester,N-(9-fluorenylmethoxycarbonyl)-3-amino-3-(4-methanesulfonyloxyphenyl)propanoicacid isopropyl ester,N-(9-fluorenylmethoxycarbonyl)-3-amino-3-(4-methanesulfonyloxyphenyl)propanoicacid t-butyl ester,N-(9-fluorenylmethoxycarbonyl)-3-amino-3-(4-methanesulfonyloxyphenyl)propanoicacid benzyl ester,N-(9-fluorenylmethoxycarbonyl)-3-amino-3-(4-benzenesulfonyloxyphenyl)propanoicacid methyl ester,N-(9-fluorenylmethoxycarbonyl)-3-amino-3-(4-benzenesulfonyloxyphenyl)propanoicacid ethyl ester,N-(9-fluorenylmethoxycarbonyl)-3-amino-3-(4-benzenesulfonyloxyphenyl)propanoicacid isopropyl ester,N-(9-fluorenylmethoxycarbonyl)-3-amino-3-(4-benzenesulfonyloxyphenyl)propanoicacid t-butyl ester,N-(9-fluorenylmethoxycarbonyl)-3-amino-3-(4-benzenesulfonyloxyphenyl)propanoicacid benzyl ester,

[0248]N-benzyloxycarbonyl-3-amino-3-(4-(p-toluenesulfonyloxy)phenyl)propanoicacid methyl ester,N-benzyloxycarbonyl-3-amino-3-(4-(p-toluenesulfonyloxy)phenyl)propanoicacid ethyl ester,N-benzyloxycarbonyl-3-amino-3-(4-(p-toluenesulfonyloxy)phenyl)propanoicacid isopropyl ester,

[0249]N-benzyloxycarbonyl-3-amino-3-(4-(p-toluenesulfonyloxy)phenyl)propanoicacid t-butyl ester,N-benzyloxycarbonyl-3-amino-3-(4-(p-toluenesulfonyloxy)phenyl)propanoicacid benzyl ester,N-benzyloxycarbonyl-3-amino-3-(4-methanesulfonyloxyphenyl)propanoic acidmethyl ester,N-benzyloxycarbonyl-3-amino-3-(4-methanesulfonyloxyphenyl)propanoic acidethyl ester,N-benzyloxycarbonyl-3-amino-3-(4-methanesulfonyloxyphenyl)propanoic acidisopropyl ester,N-benzyloxycarbonyl-3-amino-3-(4-methanesulfonyloxyphenyl)propanoic acidt-butyl ester,N-benzyloxycarbonyl-3-amino-3-(4-methanesulfonyloxyphenyl)propanoic acidbenzyl ester,N-benzyloxycarbonyl-3-amino-3-(4-benzenesulfonyloxyphenyl)propanoic acidmethyl ester,N-benzyloxycarbonyl-3-amino-3-(4-benzenesulfonyloxyphenyl)propanoic acidethyl ester,N-benzyloxycarbonyl-3-amino-3-(4-benzenesulfonyloxyphenyl)propanoic acidisopropyl ester,N-benzyloxycarbonyl-3-amino-3-(4-benzenesulfonyloxyphenyl)propanoic acidt-butyl ester,N-benzyloxycarbonyl-3-amino-3-(4-benzenesulfonyloxyphenyl)propanoic acidbenzyl ester,

[0250]N-(t-butyloxycarbonyl)-4-amino-3-(4-(p-toluenesulfonyloxy)phenyl)butanoicacid methyl ester,N-(t-butyloxycarbonyl)-4-amino-3-(4-(p-toluenesulfonyloxy)phenyl)butanoicacid ethyl ester,N-(t-butyloxycarbonyl)-4-amino-3-(4-(p-toluenesulfonyloxy)phenyl)butanoicacid isopropyl ester,N-(t-butyloxycarbonyl)-4-amino-3-(4-(p-toluenesulfonyloxy)phenyl)butanoicacid t-butyl ester,N-(t-butyloxycarbonyl)-4-amino-3-(4-(p-toluenesulfonyloxy)phenyl)butanoicacid benzyl ester,N-(t-butyloxycarbonyl)-4-amino-3-(4-methanesulfonyloxyphenyl)butanoicacid methyl ester,N-(t-butyloxycarbonyl)-4-amino-3-(4-methanesulfonyloxyphenyl)butanoicacid ethyl ester,N-(t-butyloxycarbonyl)-4-amino-3-(4-methanesulfonyloxyphenyl)butanoicacid isopropyl ester,N-(t-butyloxycarbonyl)-4-amino-3-(4-methanesulfonyloxyphenyl)butanoicacid t-butyl ester,N-(t-butyloxycarbonyl)-4-amino-3-(4-methanesulfonyloxyphenyl)butanoicacid benzyl ester,N-(t-butyloxycarbonyl)-4-amino-3-(4-benzenesulfonyloxyphenyl)butanoicacid methyl ester,N-(t-butyloxycarbonyl)-4-amino-3-(4-benzenesulfonyloxyphenyl)butanoicacid ethyl ester,N-(t-butyloxycarbonyl)-4-amino-3-(4-benzenesulfonyloxyphenyl)butanoicacid isopropyl ester,N-(t-butyloxycarbonyl)-4-amino-3-(4-benzenesulfonyloxyphenyl)butanoicacid t-butyl ester,N-(t-butyloxycarbonyl)-4-amino-3-(4-benzenesulfonyloxyphenyl)butanoicacid benzyl ester,

[0251] N-acetyl-4-amino-3-(4-(p-toluenesulfonyloxy)phenyl)butanoic acidmethyl ester,N-acetyl-4-amino-3-(4-(p-toluenesulfonyloxy)phenyl)butanoic acid ethylester, N-4-amino-3-(4-(p-toluenesulfonyloxy)phenyl)butanoic acidisopropyl ester, N-4-amino-3-(4-(p-toluenesulfonyloxy)phenyl)butanoicacid t-butyl ester,N-acetyl-4-amino-3-(4-(p-toluenesulfonyloxy)phenyl)butanoic acid benzylester, N-acetyl-4-amino-3-(4-methanesulfonyloxyphenyl)butanoic acidmethyl ester, N-acetyl-4-amino-3-(4-methanesulfonyloxyphenyl)butanoicacid ethyl ester,N-acetyl-4-amino-3-(4-methanesulfonyloxyphenyl)butanoic acid isopropylester, N-acetyl-4-amino-3-(4-methanesulfonyloxyphenyl)butanoic acidt-butyl ester, N-acetyl-4-amino-3-(4-methanesulfonyloxyphenyl)butanoicacid benzyl ester,N-acetyl-4-amino-3-(4-benzenesulfonyloxyphenyl)butanoic acid methylester, N-acetyl-4-amino-3-(4-benzenesulfonyloxyphenyl)butanoic acidethyl ester, N-acetyl-4-amino-3-(4-benzenesulfonyloxyphenyl)butanoicacid isopropyl ester,N-acetyl-4-amino-3-(4-benzenesulfonyloxyphenyl)butanoic acid t-butylester, N-acetyl-4-amino-3-(4-benzenesulfonyloxyphenyl)butanoic acidbenzyl ester,

[0252] N-benzyl-4-amino-3-(4-(p-toluenesulfonyloxy)phenyl)butanoic acidmethyl ester,N-benzyl-4-amino-3-(4-(p-toluenesulfonyloxy)phenyl)butanoic acid ethylester, N-benzyl-4-amino-3-(4-(p-toluenesulfonyloxy)phenyl)butanoic acidisopropyl ester,N-benzyl-4-amino-3-(4-(p-toluenesulfonyloxy)phenyl)butanoic acid t-butylester, N-benzyl-4-amino-3-(4-(p-toluenesulfonyloxy)phenyl)butanoic acidbenzyl ester, N-benzyl-4-amino-3-(4-methanesulfonyloxyphenyl)butanoicacid methyl ester,N-benzyl-4-amino-3-(4-methanesulfonyloxyphenyl)butanoic acid ethylester, N-benzyl-4-amino-3-(4-methanesulfonyloxyphenyl)butanoic acidisopropyl ester, N-benzyl-4-amino-3-(4-methanesulfonyloxyphenyl)butanoicacid t-butyl ester,N-benzyl-4-amino-3-(4-methanesulfonyloxyphenyl)butanoic acid benzylester, N-benzyl-4-amino-3-(4-benzenesulfonyloxyphenyl)butanoic acidmethyl ester, N-benzyl-4-amino-3-(4-benzenesulfonyloxyphenyl)butanoicacid ethyl ester,N-benzyl-4-amino-3-(4-benzenesulfonyloxyphenyl)butanoic acid isopropylester, N-benzyl-4-amino-3-(4-benzenesulfonyloxyphenyl)butanoic acidt-butyl ester, N-benzyl-4-amino-3-(4-benzenesulfonyloxyphenyl)butanoicacid benzyl ester,

[0253]N-(9-fluorenylmethoxycarbonyl)-4-amino-3-(4-(p-toluenesulfonyloxy)phenyl)butanoicacid methyl ester,N-(9-fluorenylmethoxycarbonyl)-4-amino-3-(4-(p-toluenesulfonyloxy)phenyl)butanoicacid ethyl ester,N-(9-fluorenylmethoxycarbonyl)-4-amino-3-(4-(p-toluenesulfonyloxy)phenyl)butanoicacid isopropyl ester,N-(9-fluorenylmethoxycarbonyl)-4-amino-3-(4-(p-toluenesulfonyloxy)phenyl)butanoicacid t-butyl ester,N-(9-fluorenylmethoxycarbonyl)-4-amino-3-(4-(p-toluenesulfonyloxy)phenyl)butanoicacid benzyl ester,N-(9-fluorenylmethoxycarbonyl)-4-amino-3-(4-methanesulfonyloxyphenyl)butanoicacid methyl ester,N-(9-fluorenylmethoxycarbonyl)-4-amino-3-(4-methanesulfonyloxyphenyl)butanoicacid ethyl ester,N-(9-fluorenylmethoxycarbonyl)-4-amino-3-(4-methanesulfonyloxyphenyl)butanoicacid isopropyl ester,N-(9-fluorenylmethoxycarbonyl)-4-amino-3-(4-methanesulfonyloxyphenyl)butanoicacid t-butyl ester,N-(9-fluorenylmethoxycarbonyl)-4-amino-3-(4-methanesulfonyloxyphenyl)butanoicacid benzyl ester,N-(9-fluorenylmethoxycarbonyl)-4-amino-3-(4-benzenesulfonyloxyphenyl)butanoicacid methyl ester,N-(9-fluorenylmethoxycarbonyl)-4-amino-3-(4-benzenesulfonyloxyphenyl)butanoicacid ethyl ester,N-(9-fluorenylmethoxycarbonyl)-4-amino-3-(4-benzenesulfonyloxyphenyl)butanoicacid isopropyl ester,N-(9-fluorenylmethoxycarbonyl)-4-amino-3-(4-benzenesulfonyloxyphenyl)butanoicacid t-butyl ester,N-(9-fluorenylmethoxycarbonyl)-4-amino-3-(4-benzenesulfonyloxyphenyl)butanoicacid benzyl ester,

[0254]N-benzyloxycarbonyl-4-amino-3-(4-(p-toluenesulfonyloxy)phenyl)butanoicacid methyl ester,N-benzyloxycarbonyl-4-amino-3-(4-(p-toluenesulfonyloxy)phenyl)butanoicacid ethyl ester,N-benzyloxycarbonyl-4-amino-3-(4-(p-toluenesulfonyloxy)phenyl)butanoicacid isopropyl ester,N-benzyloxycarbonyl-4-amino-3-(4-(p-toluenesulfonyloxy)phenyl)butanoicacid t-butyl ester,N-benzyloxycarbonyl-4-amino-3-(4-(p-toluenesulfonyloxy)phenyl)butanoicacid benzyl ester,N-benzyloxycarbonyl-4-amino-3-(4-methanesulfonyloxyphenyl)butanoic acidmethyl ester,N-benzyloxycarbonyl-4-amino-3-(4-methanesulfonyloxyphenyl)butanoic acidethyl ester,N-benzyloxycarbonyl-4-amino-3-(4-methanesulfonyloxyphenyl)butanoic acidisopropyl ester,N-benzyloxycarbonyl-4-amino-3-(4-methanesulfonyloxyphenyl)butanoic acidt-butyl ester,N-benzyloxycarbonyl-4-amino-3-(4-methanesulfonyloxyphenyl)butanoic acidbenzyl ester,N-benzyloxycarbonyl-4-amino-3-(4-benzenesulfonyloxyphenyl)butanoic acidmethyl ester,N-benzyloxycarbonyl-4-amino-3-(4-benzenesulfonyloxyphenyl)butanoic acidethyl ester,N-benzyloxycarbonyl-4-amino-3-(4-benzenesulfonyloxyphenyl)butanoic acidisopropyl ester,N-benzyloxycarbonyl-4-amino-3-(4-benzenesulfonyloxyphenyl)butanoic acidt-butyl ester,N-benzyloxycarbonyl-4-amino-3-(4-benzenesulfonyloxyphenyl)butanoic acidbenzyl ester,

[0255]N-(t-butyloxycarbonyl)-4-amino-3-(3-(p-toluenesulfonyloxy)phenyl)butanoicacid methyl ester,N-(t-butyloxycarbonyl)-4-amino-3-(3-(p-toluenesulfonyloxy)phenyl)butanoicacid ethyl ester,N-(t-butyloxycarbonyl)-4-amino-3-(3-(p-toluenesulfonyloxy)phenyl)butanoicacid isopropyl ester,N-(t-butyloxycarbonyl)-4-amino-3-(3-(p-toluenesulfonyloxy)phenyl)butanoicacid t-butyl ester,N-(t-butyloxycarbonyl)-4-amino-3-(3-(p-toluenesulfonyloxy)phenyl)butanoicacid benzyl ester,N-(t-butyloxycarbonyl)-4-amino-3-(3-methanesulfonyloxyphenyl)butanoicacid methyl ester,N-(t-butyloxycarbonyl)-4-amino-3-(3-methanesulfonyloxyphenyl)butanoicacid ethyl ester,N-(t-butyloxycarbonyl)-4-amino-3-(3-methanesulfonyloxyphenyl)butanoicacid isopropyl ester,N-(t-butyloxycarbonyl)-4-amino-3-(3-methanesulfonyloxyphenyl)butanoicacid t-butyl ester,N-(t-butyloxycarbonyl)-4-amino-3-(3-methanesulfonyloxyphenyl)butanoicacid benzyl ester,N-(t-butyloxycarbonyl)-4-amino-3-(3-benzenesulfonyloxyphenyl)butanoicacid methyl ester,N-(t-butyloxycarbonyl)-4-amino-3-(3-benzenesulfonyloxyphenyl)butanoicacid ethyl ester,N-(t-butyloxycarbonyl)-4-amino-3-(3-benzenesulfonyloxyphenyl)butanoicacid isopropyl ester,N-(t-butyloxycarbonyl)-4-amino-3-(3-benzenesulfonyloxyphenyl)butanoicacid t-butyl ester,N-(t-butyloxycarbonyl)-4-amino-3-(3-benzenesulfonyloxyphenyl)butanoicacid benzyl ester,

[0256] N-acetyl-4-amino-3-(3-(p-toluenesulfonyloxy)phenyl)butanoic acidmethyl ester,N-acetyl-4-amino-3-(3-(p-toluenesulfonyloxy)phenyl)butanoic acid ethylester, N-4-amino-3-(3-(p-toluenesulfonyloxy)phenyl)butanoic acidisopropyl ester, N-4-amino-3-(3-(p-toluenesulfonyloxy)phenyl)butanoicacid t-butyl ester,N-acetyl-4-amino-3-(3-(p-toluenesulfonyloxy)phenyl)butanoic acid benzylester, N-acetyl-4-amino-3-(3-methanesulfonyloxyphenyl)butanoic acidmethyl ester, N-acetyl-4-amino-3-(3-methanesulfonyloxyphenyl)butanoicacid ethyl ester,N-acetyl-4-amino-3-(3-methanesulfonyloxyphenyl)butanoic acid isopropylester, N-acetyl-4-amino-3-(3-methanesulfonyloxyphenyl)butanoic acidt-butyl ester, N-acetyl-4-amino-3-(3-methanesulfonyloxyphenyl)butanoicacid benzyl ester,N-acetyl-4-amino-3-(3-benzenesulfonyloxyphenyl)butanoic acid methylester, N-acetyl-4-amino-3-(3-benzenesulfonyloxyphenyl)butanoic acidethyl ester, N-acetyl-4-amino-3-(3-benzenesulfonyloxyphenyl)butanoicacid isopropyl ester,N-acetyl-4-amino-3-(3-benzenesulfonyloxyphenyl)butanoic acid t-butylester, N-acetyl-4-amino-3-(3-benzenesulfonyloxyphenyl)butanoic acidbenzyl ester,

[0257] N-benzyl-4-amino-3-(3-(p-toluenesulfonyloxy)phenyl)butanoic acidmethyl ester,N-benzyl-4-amino-3-(3-(p-toluenesulfonyloxy)phenyl)butanoic acid ethylester, N-benzyl-4-amino-3-(3-(p-toluenesulfonyloxy)phenyl)butanoic acidisopropyl ester,N-benzyl-4-amino-3-(3-(p-toluenesulfonyloxy)phenyl)butanoic acid t-butylester, N-benzyl-4-amino-3-(3-(p-toluenesulfonyloxy)phenyl)butanoic acidbenzyl ester, N-benzyl-4-amino-3-(3-methanesulfonyloxyphenyl)butanoicacid methyl ester,N-benzyl-4-amino-3-(3-methanesulfonyloxyphenyl)butanoic acid ethylester, N-benzyl-4-amino-3-(3-methanesulfonyloxyphenyl)butanoic acidisopropyl ester, N-benzyl-4-amino-3-(3-methanesulfonyloxyphenyl)butanoicacid t-butyl ester,N-benzyl-4-amino-3-(3-methanesulfonyloxyphenyl)butanoic acid benzylester, N-benzyl-4-amino-3-(3-benzenesulfonyloxyphenyl)butanoic acidmethyl ester, N-benzyl-4-amino-3-(3-benzenesulfonyloxyphenyl)butanoicacid ethyl ester,N-benzyl-4-amino-3-(3-benzenesulfonyloxyphenyl)butanoic acid isopropylester, N-benzyl-4-amino-3-(3-benzenesulfonyloxyphenyl)butanoic acidt-butyl ester, N-benzyl-4-amino-3-(3-benzenesulfonyloxyphenyl)butanoicacid benzyl ester,

[0258]N-(9-fluorenylmethoxycarbonyl)-4-amino-3-(3-(p-toluenesulfonyloxy)phenyl)butanoicacid methyl ester,N-(9-fluorenylmethoxycarbonyl)-4-amino-3-(3-(p-toluenesulfonyloxy)phenyl)butanoicacid ethyl ester,N-(9-fluorenylmethoxycarbonyl)-4-amino-3-(3-(p-toluenesulfonyloxy)phenyl)butanoicacid isopropyl ester,N-(9-fluorenylmethoxycarbonyl)-4-amino-3-(3-(p-toluenesulfonyloxy)phenyl)butanoicacid t-butyl ester,N-(9-fluorenylmethoxycarbonyl)-4-amino-3-(3-(p-toluenesulfonyloxy)phenyl)butanoicacid benzyl ester,N-(9-fluorenylmethoxycarbonyl)-4-amino-3-(3-methanesulfonyloxyphenyl)butanoicacid methyl ester,N-(9-fluorenylmethoxycarbonyl)-4-amino-3-(3-methanesulfonyloxyphenyl)butanoicacid ethyl ester,N-(9-fluorenylmethoxycarbonyl)-4-amino-3-(3-methanesulfonyloxyphenyl)butanoicacid isopropyl ester,N-(9-fluorenylmethoxycarbonyl)-4-amino-3-(3-methanesulfonyloxyphenyl)butanoicacid t-butyl ester,N-(9-fluorenylmethoxycarbonyl)-4-amino-3-(3-methanesulfonyloxyphenyl)butanoicacid benzyl ester,N-(9-fluorenylmethoxycarbonyl)-4-amino-3-(3-benzenesulfonyloxyphenyl)butanoicacid methyl ester,N-(9-fluorenylmethoxycarbonyl)-4-amino-3-(3-benzenesulfonyloxyphenyl)butanoicacid ethyl ester,N-(9-fluorenylmethoxycarbonyl)-4-amino-3-(3-benzenesulfonyloxyphenyl)butanoicacid isopropyl ester,N-(9-fluorenylmethoxycarbonyl)-4-amino-3-(3-benzenesulfonyloxyphenyl)butanoicacid t-butyl ester,N-(9-fluorenylmethoxycarbonyl)-4-amino-3-(3-benzenesulfonyloxyphenyl)butanoicacid benzyl ester,

[0259]N-benzyloxycarbonyl-4-amino-3-(3-(p-toluenesulfonyloxy)phenyl)butanoicacid methyl ester,N-benzyloxycarbonyl-4-amino-3-(3-(p-toluenesulfonyloxy)phenyl)butanoicacid ethyl ester,N-benzyloxycarbonyl-4-amino-3-(3-(p-toluenesulfonyloxy)phenyl)butanoicacid isopropyl ester,N-benzyloxycarbonyl-4-amino-3-(3-(p-toluenesulfonyloxy)phenyl)butanoicacid t-butyl ester,N-benzyloxycarbonyl-4-amino-3-(3-(p-toluenesulfonyloxy)phenyl)butanoicacid benzyl ester,N-benzyloxycarbonyl-4-amino-3-(3-methanesulfonyloxyphenyl)butanoic acidmethyl ester,N-benzyloxycarbonyl-4-amino-3-(3-methanesulfonyloxyphenyl)butanoic acidethyl ester,N-benzyloxycarbonyl-4-amino-3-(3-methanesulfonyloxyphenyl)butanoic acidisopropyl ester,N-benzyloxycarbonyl-4-amino-3-(3-methanesulfonyloxyphenyl)butanoic acidt-butyl ester,N-benzyloxycarbonyl-4-amino-3-(3-methanesulfonyloxyphenyl)butanoic acidbenzyl ester,N-benzyloxycarbonyl-4-amino-3-(3-benzenesulfonyloxyphenyl)butanoic acidmethyl ester,N-benzyloxycarbonyl-4-amino-3-(3-benzenesulfonyloxyphenyl)butanoic acidethyl ester,N-benzyloxycarbonyl-4-amino-3-(3-benzenesulfonyloxyphenyl)butanoic acidisopropyl ester,N-benzyloxycarbonyl-4-amino-3-(3-benzenesulfonyloxyphenyl)butanoic acidt-butyl ester,N-benzyloxycarbonyl-4-amino-3-(3-benzenesulfonyloxyphenyl)butanoic acidbenzyl ester,

[0260]N-(t-butyloxycarbonyl)-3-amino-2-(4-(p-toluenesulfonyloxy)phenyl)propanoicacid methyl ester,N-(t-butyloxycarbonyl)-3-amino-2-(4-(p-toluenesulfonyloxy)phenyl)propanoicacid ethyl ester,N-(t-butyloxycarbonyl)-3-amino-2-(4-(p-toluenesulfonyloxy)phenyl)propanoicacid isopropyl ester,

[0261]N-(t-butyloxycarbonyl)-3-amino-2-(4-(p-toluenesulfonyloxy)phenyl)propanoicacid t-butyl ester,N-(t-butyloxycarbonyl)-3-amino-2-(4-(p-toluenesulfonyloxy)phenyl)propanoicacid benzyl ester,N-(t-butyloxycarbonyl)-3-amino-2-(4-methanesulfonyloxyphenyl)propanoicacid methyl ester,N-(t-butyloxycarbonyl)-3-amino-2-(4-methanesulfonyloxyphenyl)propanoicacid ethyl ester,N-(t-butyloxycarbonyl)-3-amino-2-(4-methanesulfonyloxyphenyl)propanoicacid isopropyl ester,N-(t-butyloxycarbonyl)-3-amino-2-(4-methanesulfonyloxyphenyl)propanoicacid t-butyl ester,N-(t-butyloxycarbonyl)-3-amino-2-(4-methanesulfonyloxyphenyl)propanoicacid benzyl ester,N-(t-butyloxycarbonyl)-3-amino-2-(4-benzenesulfonyloxyphenyl)propanoicacid methyl ester,N-(t-butyloxycarbonyl)-3-amino-2-(4-benzenesulfonyloxyphenyl)propanoicacid ethyl ester,N-(t-butyloxycarbonyl)-3-amino-2-(4-benzenesulfonyloxyphenyl)propanoicacid isopropyl ester,N-(t-butyloxycarbonyl)-3-amino-2-(4-benzenesulfonyloxyphenyl)propanoicacid t-butyl ester,N-(t-butyloxycarbonyl)-3-amino-2-(4-benzenesulfonyloxyphenyl)propanoicacid benzyl ester,

[0262] N-acetyl-3-amino-2-(4-(p-toluenesulfonyloxy)phenyl)propanoic acidmethyl ester,N-acetyl-3-amino-2-(4-(p-toluenesulfonyloxy)phenyl)propanoic acid ethylester, N-3-amino-2-(4-(p-toluenesulfonyloxy)phenyl)propanoic acidisopropyl ester,

[0263] N-3-amino-2-(4-(p-toluenesulfonyloxy)phenyl)propanoic acidt-butyl ester,N-acetyl-3-amino-2-(4-(p-toluenesulfonyloxy)phenyl)propanoic acid benzylester, N-acetyl-3-amino-2-(4-methanesulfonyloxyphenyl)propanoic acidmethyl ester, N-acetyl-3-amino-2-(4-methanesulfonyloxyphenyl)propanoicacid ethyl ester,N-acetyl-3-amino-2-(4-methanesulfonyloxyphenyl)propanoic acid isopropylester, N-acetyl-3-amino-2-(4-methanesulfonyloxyphenyl)propanoic acidt-butyl ester, N-acetyl-3-amino-2-(4-methanesulfonyloxyphenyl)propanoicacid benzyl ester,N-acetyl-3-amino-2-(4-benzenesulfonyloxyphenyl)propanoic acid methylester, N-acetyl-3-amino-2-(4-benzenesulfonyloxyphenyl)propanoic acidethyl ester, N-acetyl-3-amino-2-(4-benzenesulfonyloxyphenyl)propanoicacid isopropyl ester,N-acetyl-3-amino-2-(4-benzenesulfonyloxyphenyl)propanoic acid t-butylester, N-acetyl-3-amino-2-(4-benzenesulfonyloxyphenyl)propanoic acidbenzyl ester,

[0264] N-benzyl-3-amino-2-(4-(p-toluenesulfonyloxy)phenyl)propanoic acidmethyl ester,N-benzyl-3-amino-2-(4-(p-toluenesulfonyloxy)phenyl)propanoic acid ethylester, N-benzyl-3-amino-2-(4-(p-toluenesulfonyloxy)phenyl)propanoic acidisopropyl ester,

[0265] N-benzyl-3-amino-2-(4-(p-toluenesulfonyloxy)phenyl)propanoic acidt-butyl ester,N-benzyl-3-amino-2-(4-(p-toluenesulfonyloxy)phenyl)propanoic acid benzylester, N-benzyl-3-amino-2-(4-methanesulfonyloxyphenyl)propanoic acidmethyl ester, N-benzyl-3-amino-2-(4-methanesulfonyloxyphenyl)propanoicacid ethyl ester,N-benzyl-3-amino-2-(4-methanesulfonyloxyphenyl)propanoic acid isopropylester, N-benzyl-3-amino-2-(4-methanesulfonyloxyphenyl)propanoic acidt-butyl ester, N-benzyl-3-amino-2-(4-methanesulfonyloxyphenyl)propanoicacid benzyl ester,N-benzyl-3-amino-2-(4-benzenesulfonyloxyphenyl)propanoic acid methylester, N-benzyl-3-amino-2-(4-benzenesulfonyloxyphenyl)propanoic acidethyl ester, N-benzyl-3-amino-2-(4-benzenesulfonyloxyphenyl)propanoicacid isopropyl ester,N-benzyl-3-amino-2-(4-benzenesulfonyloxyphenyl)propanoic acid t-butylester, N-benzyl-3-amino-2-(4-benzenesulfonyloxyphenyl)propanoic acidbenzyl ester,

[0266]N-(9-fluorenylmethoxycarbonyl)-3-amino-2-(4-(p-toluenesulfonyloxy)phenyl)propanoicacid methyl ester,N-(9-fluorenylmethoxycarbonyl)-3-amino-2-(4-(p-toluenesulfonyloxy)phenyl)propanoicacid ethyl ester,N-(9-fluorenylmethoxycarbonyl)-3-amino-2-(4-(p-toluenesulfonyloxy)phenyl)propanoicacid isopropyl ester,

[0267]N-(9-fluorenylmethoxycarbonyl)-3-amino-2-(4-(p-toluenesulfonyloxy)phenyl)propanoicacid t-butyl ester,N-(9-fluorenylmethoxycarbonyl)-3-amino-2-(4-(p-toluenesulfonyloxy)phenyl)propanoicacid benzyl ester,N-(9-fluorenylmethoxycarbonyl)-3-amino-2-(4-methanesulfonyloxyphenyl)propanoicacid methyl ester,N-(9-fluorenylmethoxycarbonyl)-3-amino-2-(4-methanesulfonyloxyphenyl)propanoicacid ethyl ester,N-(9-fluorenylmethoxycarbonyl)-3-amino-2-(4-methanesulfonyloxyphenyl)propanoicacid isopropyl ester,N-(9-fluorenylmethoxycarbonyl)-3-amino-2-(4-methanesulfonyloxyphenyl)propanoicacid t-butyl ester,N-(9-fluorenylmethoxycarbonyl)-3-amino-2-(4-methanesulfonyloxyphenyl)propanoicacid benzyl ester,N-(9-fluorenylmethoxycarbonyl)-3-amino-2-(4-benzenesulfonyloxyphenyl)propanoicacid methyl ester,N-(9-fluorenylmethoxycarbonyl)-3-amino-2-(4-benzenesulfonyloxyphenyl)propanoicacid ethyl ester,N-(9-fluorenylmethoxycarbonyl)-3-amino-2-(4-benzenesulfonyloxyphenyl)propanoicacid isopropyl ester,N-(9-fluorenylmethoxycarbonyl)-3-amino-2-(4-benzenesulfonyloxyphenyl)propanoicacid t-butyl ester,N-(9-fluorenylmethoxycarbonyl)-3-amino-2-(4-benzenesulfonyloxyphenyl)propanoicacid benzyl ester,

[0268]N-benzyloxycarbonyl-3-amino-2-(4-(p-toluenesulfonyloxy)phenyl)propanoicacid methyl ester,N-benzyloxycarbonyl-3-amino-2-(4-(p-toluenesulfonyloxy)phenyl)propanoicacid ethyl ester,N-benzyloxycarbonyl-3-amino-2-(4-(p-toluenesulfonyloxy)phenyl)propanoicacid isopropyl ester,

[0269]N-benzyloxycarbonyl-3-amino-2-(4-(p-toluenesulfonyloxy)phenyl)propanoicacid t-butyl ester,N-benzyloxycarbonyl-3-amino-2-(4-(p-toluenesulfonyloxy)phenyl)propanoicacid benzyl ester,N-benzyloxycarbonyl-3-amino-2-(4-methanesulfonyloxyphenyl)propanoic acidmethyl ester,N-benzyloxycarbonyl-3-amino-2-(4-methanesulfonyloxyphenyl)propanoic acidethyl ester,N-benzyloxycarbonyl-3-amino-2-(4-methanesulfonyloxyphenyl)propanoic acidisopropyl ester,N-benzyloxycarbonyl-3-amino-2-(4-methanesulfonyloxyphenyl)propanoic acidt-butyl ester,N-benzyloxycarbonyl-3-amino-2-(4-methanesulfonyloxyphenyl)propanoic acidbenzyl ester,N-benzyloxycarbonyl-3-amino-2-(4-benzenesulfonyloxyphenyl)propanoic acidmethyl ester,N-benzyloxycarbonyl-3-amino-2-(4-benzenesulfonyloxyphenyl)propanoic acidethyl ester,N-benzyloxycarbonyl-3-amino-2-(4-benzenesulfonyloxyphenyl)propanoic acidisopropyl ester,N-benzyloxycarbonyl-3-amino-2-(4-benzenesulfonyloxyphenyl)propanoic acidt-butyl ester,N-benzyloxycarbonyl-3-amino-2-(4-benzenesulfonyloxyphenyl)propanoic acidbenzyl ester,

[0270]N-(t-butyloxycarbonyl)-3-amino-2-(3-(p-toluenesulfonyloxy)phenyl)propanoicacid methyl ester,N-(t-butyloxycarbonyl)-3-amino-2-(3-(p-toluenesulfonyloxy)phenyl)propanoicacid ethyl ester,N-(t-butyloxycarbonyl)-3-amino-2-(3-(p-toluenesulfonyloxy)phenyl)propanoicacid isopropyl ester,

[0271]N-(t-butyloxycarbonyl)-3-amino-2-(3-(p-toluenesulfonyloxy)phenyl)propanoicacid t-butyl ester,N-(t-butyloxycarbonyl)-3-amino-2-(3-(p-toluenesulfonyloxy)phenyl)propanoicacid benzyl ester,N-(t-butyloxycarbonyl)-3-amino-2-(3-methanesulfonyloxyphenyl)propanoicacid methyl ester,N-(t-butyloxycarbonyl)-3-amino-2-(3-methanesulfonyloxyphenyl)propanoicacid ethyl ester,N-(t-butyloxycarbonyl)-3-amino-2-(3-methanesulfonyloxyphenyl)propanoicacid isopropyl ester,N-(t-butyloxycarbonyl)-3-amino-2-(3-methanesulfonyloxyphenyl)propanoicacid t-butyl ester,N-(t-butyloxycarbonyl)-3-amino-2-(3-methanesulfonyloxyphenyl)propanoicacid benzyl ester,N-(t-butyloxycarbonyl)-3-amino-2-(3-benzenesulfonyloxyphenyl)propanoicacid methyl ester,N-(t-butyloxycarbonyl)-3-amino-2-(3-benzenesulfonyloxyphenyl)propanoicacid ethyl ester,N-(t-butyloxycarbonyl)-3-amino-2-(3-benzenesulfonyloxyphenyl)propanoicacid isopropyl ester,N-(t-butyloxycarbonyl)-3-amino-2-(3-benzenesulfonyloxyphenyl)propanoicacid t-butyl ester,N-(t-butyloxycarbonyl)-3-amino-2-(3-benzenesulfonyloxyphenyl)propanoicacid benzyl ester,

[0272] N-acetyl-3-amino-2-(3-(p-toluenesulfonyloxy)phenyl)propanoic acidmethyl ester,N-acetyl-3-amino-2-(3-(p-toluenesulfonyloxy)phenyl)propanoic acid ethylester, N-3-amino-2-(3-(p-toluenesulfonyloxy)phenyl)propanoic acidisopropyl ester,

[0273] N-3-amino-2-(3-(p-toluenesulfonyloxy)phenyl)propanoic acidt-butyl ester,N-acetyl-3-amino-2-(3-(p-toluenesulfonyloxy)phenyl)propanoic acid benzylester, N-acetyl-3-amino-2-(3-methanesulfonyloxyphenyl)propanoic acidmethyl ester, N-acetyl-3-amino-2-(3-methanesulfonyloxyphenyl)propanoicacid ethyl ester,N-acetyl-3-amino-2-(3-methanesulfonyloxyphenyl)propanoic acid isopropylester, N-acetyl-3-amino-2-(3-methanesulfonyloxyphenyl)propanoic acidt-butyl ester, N-acetyl-3-amino-2-(3-methanesulfonyloxyphenyl)propanoicacid benzyl ester,N-acetyl-3-amino-2-(3-benzenesulfonyloxyphenyl)propanoic acid methylester, N-acetyl-3-amino-2-(3-benzenesulfonyloxyphenyl)propanoic acidethyl ester, N-acetyl-3-amino-2-(3-benzenesulfonyloxyphenyl)propanoicacid isopropyl ester,N-acetyl-3-amino-2-(3-benzenesulfonyloxyphenyl)propanoic acid t-butylester, N-acetyl-3-amino-2-(3-benzenesulfonyloxyphenyl)propanoic acidbenzyl ester,

[0274] N-benzyl-3-amino-2-(3-(p-toluenesulfonyloxy)phenyl)propanoic acidmethyl ester,N-benzyl-3-amino-2-(3-(p-toluenesulfonyloxy)phenyl)propanoic acid ethylester, N-benzyl-3-amino-2-(3-(p-toluenesulfonyloxy)phenyl)propanoic acidisopropyl ester,

[0275] N-benzyl-3-amino-2-(3-(p-toluenesulfonyloxy)phenyl)propanoic acidt-butyl ester,N-benzyl-3-amino-2-(3-(p-toluenesulfonyloxy)phenyl)propanoic acid benzylester, N-benzyl-3-amino-2-(3-methanesulfonyloxyphenyl)propanoic acidmethyl ester, N-benzyl-3-amino-2-(3-methanesulfonyloxyphenyl)propanoicacid ethyl ester,N-benzyl-3-amino-2-(3-methanesulfonyloxyphenyl)propanoic acid isopropylester, N-benzyl-3-amino-2-(3-methanesulfonyloxyphenyl)propanoic acidt-butyl ester, N-benzyl-3-amino-2-(3-methanesulfonyloxyphenyl)propanoicacid benzyl ester,N-benzyl-3-amino-2-(3-benzenesulfonyloxyphenyl)propanoic acid methylester, N-benzyl-3-amino-2-(3-benzenesulfonyloxyphenyl)propanoic acidethyl ester, N-benzyl-3-amino-2-(3-benzenesulfonyloxyphenyl)propanoicacid isopropyl ester,N-benzyl-3-amino-2-(3-benzenesulfonyloxyphenyl)propanoic acid t-butylester, N-benzyl-3-amino-2-(3-benzenesulfonyloxyphenyl)propanoic acidbenzyl ester,

[0276]N-(9-fluorenylmethoxycarbonyl)-3-amino-2-(3-(p-toluenesulfonyloxy)phenyl)propanoicacid methyl ester,N-(9-fluorenylmethoxycarbonyl)-3-amino-2-(3-(p-toluenesulfonyloxy)phenyl)propanoicacid ethyl ester,N-(9-fluorenylmethoxycarbonyl)-3-amino-2-(3-(p-toluenesulfonyloxy)phenyl)propanoicacid isopropyl ester,

[0277]N-(9-fluorenylmethoxycarbonyl)-3-amino-2-(3-(p-toluenesulfonyloxy)phenyl)propanoicacid t-butyl ester,N-(9-fluorenylmethoxycarbonyl)-3-amino-2-(3-(p-toluenesulfonyloxy)phenyl)propanoicacid benzyl ester,N-(9-fluorenylmethoxycarbonyl)-3-amino-2-(3-methanesulfonyloxyphenyl)propanoicacid methyl ester,N-(9-fluorenylmethoxycarbonyl)-3-amino-2-(3-methanesulfonyloxyphenyl)propanoicacid ethyl ester,N-(9-fluorenylmethoxycarbonyl)-3-amino-2-(3-methanesulfonyloxyphenyl)propanoicacid isopropyl ester,N-(9-fluorenylmethoxycarbonyl)-3-amino-2-(3-methanesulfonyloxyphenyl)propanoicacid t-butyl ester,N-(9-fluorenylmethoxycarbonyl)-3-amino-2-(3-methanesulfonyloxyphenyl)propanoicacid benzyl ester,N-(9-fluorenylmethoxycarbonyl)-3-amino-2-(3-benzenesulfonyloxyphenyl)propanoicacid methyl ester,N-(9-fluorenylmethoxycarbonyl)-3-amino-2-(3-benzenesulfonyloxyphenyl)propanoicacid ethyl ester,N-(9-fluorenylmethoxycarbonyl)-3-amino-2-(3-benzenesulfonyloxyphenyl)propanoicacid isopropyl ester,N-(9-fluorenylmethoxycarbonyl)-3-amino-2-(3-benzenesulfonyloxyphenyl)propanoicacid t-butyl ester,N-(9-fluorenylmethoxycarbonyl)-3-amino-2-(3-benzenesulfonyloxyphenyl)propanoicacid benzyl ester,

[0278]N-benzyloxycarbonyl-3-amino-2-(3-(p-toluenesulfonyloxy)phenyl)propanoicacid methyl ester,N-benzyloxycarbonyl-3-amino-2-(3-(p-toluenesulfonyloxy)phenyl)propanoicacid ethyl ester,N-benzyloxycarbonyl-3-amino-2-(3-(p-toluenesulfonyloxy)phenyl)propanoicacid isopropyl ester,

[0279]N-benzyloxycarbonyl-3-amino-2-(3-(p-toluenesulfonyloxy)phenyl)propanoicacid t-butyl ester,N-benzyloxycarbonyl-3-amino-2-(3-(p-toluenesulfonyloxy)phenyl)propanoicacid benzyl ester,N-benzyloxycarbonyl-3-amino-2-(3-methanesulfonyloxyphenyl)propanoic acidmethyl ester,N-benzyloxycarbonyl-3-amino-2-(3-methanesulfonyloxyphenyl)propanoic acidethyl ester,N-benzyloxycarbonyl-3-amino-2-(3-methanesulfonyloxyphenyl)propanoic acidisopropyl ester,N-benzyloxycarbonyl-3-amino-2-(3-methanesulfonyloxyphenyl)propanoic acidt-butyl ester,N-benzyloxycarbonyl-3-amino-2-(3-methanesulfonyloxyphenyl)propanoic acidbenzyl ester,N-benzyloxycarbonyl-3-amino-2-(3-benzenesulfonyloxyphenyl)propanoic acidmethyl ester,N-benzyloxycarbonyl-3-amino-2-(3-benzenesulfonyloxyphenyl)propanoic acidethyl ester,N-benzyloxycarbonyl-3-amino-2-(3-benzenesulfonyloxyphenyl)propanoic acidisopropyl ester,N-benzyloxycarbonyl-3-amino-2-(3-benzenesulfonyloxyphenyl)propanoic acidt-butyl ester,N-benzyloxycarbonyl-3-amino-2-(3-benzenesulfonyloxyphenyl)propanoic acidbenzyl ester,

[0280]N-(t-butyloxycarbonyl)-3-amino-4-(4-(p-toluenesulfonyloxy)phenyl)butanoicacid methyl ester,N-(t-butyloxycarbonyl)-3-amino-4-(4-(p-toluenesulfonyloxy)phenyl)butanoicacid ethyl ester,N-(t-butyloxycarbonyl)-3-amino-4-(4-(p-toluenesulfonyloxy)phenyl)butanoicacid isopropyl ester,N-(t-butyloxycarbonyl)-3-amino-4-(4-(p-toluenesulfonyloxy)phenyl)butanoicacid t-butyl ester,N-(t-butyloxycarbonyl)-3-amino-4-(4-(p-toluenesulfonyloxy)phenyl)butanoicacid benzyl ester,N-(t-butyloxycarbonyl)-3-amino-4-(4-methanesulfonyloxyphenyl)butanoicacid methyl ester,N-(t-butyloxycarbonyl)-3-amino-4-(4-methanesulfonyloxyphenyl)butanoicacid ethyl ester,N-(t-butyloxycarbonyl)-3-amino-4-(4-methanesulfonyloxyphenyl)butanoicacid isopropyl ester,N-(t-butyloxycarbonyl)-3-amino-4-(4-methanesulfonyloxyphenyl)butanoicacid t-butyl ester,N-(t-butyloxycarbonyl)-3-amino-4-(4-methanesulfonyloxyphenyl)butanoicacid benzyl ester,N-(t-butyloxycarbonyl)-3-amino-4-(4-benzenesulfonyloxyphenyl)butanoicacid methyl ester,N-(t-butyloxycarbonyl)-3-amino-4-(4-benzenesulfonyloxyphenyl)butanoicacid ethyl ester,N-(t-butyloxycarbonyl)-3-amino-4-(4-benzenesulfonyloxyphenyl)butanoicacid isopropyl ester,N-(t-butyloxycarbonyl)-3-amino-4-(4-benzenesulfonyloxyphenyl)butanoicacid t-butyl ester,N-(t-butyloxycarbonyl)-3-amino-4-(4-benzenesulfonyloxyphenyl)butanoicacid benzyl ester,

[0281] N-acetyl-3-amino-4-(4-(p-toluenesulfonyloxy)phenyl)butanoic acidmethyl ester,N-acetyl-3-amino-4-(4-(p-toluenesulfonyloxy)phenyl)butanoic acid ethylester, N-3-amino-4-(4-(p-toluenesulfonyloxy)phenyl)butanoic acidisopropyl ester, N-3-amino-4-(4-(p-toluenesulfonyloxy)phenyl)butanoicacid t-butyl ester,N-acetyl-3-amino-4-(4-(p-toluenesulfonyloxy)phenyl)butanoic acid benzylester, N-acetyl-3-amino-4-(4-methanesulfonyloxyphenyl)butanoic acidmethyl ester, N-acetyl-3-amino-4-(4-methanesulfonyloxyphenyl)butanoicacid ethyl ester,N-acetyl-3-amino-4-(4-methanesulfonyloxyphenyl)butanoic acid isopropylester, N-acetyl-3-amino-4-(4-methanesulfonyloxyphenyl)butanoic acidt-butyl ester, N-acetyl-3-amino-4-(4-methanesulfonyloxyphenyl)butanoicacid benzyl ester,N-acetyl-3-amino-4-(4-benzenesulfonyloxyphenyl)butanoic acid methylester, N-acetyl-3-amino-4-(4-benzenesulfonyloxyphenyl)butanoic acidethyl ester, N-acetyl-3-amino-4-(4-benzenesulfonyloxyphenyl)butanoicacid isopropyl ester,N-acetyl-3-amino-4-(4-benzenesulfonyloxyphenyl)butanoic acid t-butylester, N-acetyl-3-amino-4-(4-benzenesulfonyloxyphenyl)butanoic acidbenzyl ester,

[0282] N-benzyl-3-amino-4-(4-(p-toluenesulfonyloxy)phenyl)butanoic acidmethyl ester,N-benzyl-3-amino-4-(4-(p-toluenesulfonyloxy)phenyl)butanoic acid ethylester, N-benzyl-3-amino-4-(4-(p-toluenesulfonyloxy)phenyl)butanoic acidisopropyl ester,N-benzyl-3-amino-4-(4-(p-toluenesulfonyloxy)phenyl)butanoic acid t-butylester, N-benzyl-3-amino-4-(4-(p-toluenesulfonyloxy)phenyl)butanoic acidbenzyl ester, N-benzyl-3-amino-4-(4-methanesulfonyloxyphenyl)butanoicacid methyl ester,N-benzyl-3-amino-4-(4-methanesulfonyloxyphenyl)butanoic acid ethylester, N-benzyl-3-amino-4-(4-methanesulfonyloxyphenyl)butanoic acidisopropyl ester, N-benzyl-3-amino-4-(4-methanesulfonyloxyphenyl)butanoicacid t-butyl ester,N-benzyl-3-amino-4-(4-methanesulfonyloxyphenyl)butanoic acid benzylester, N-benzyl-3-amino-4-(4-benzenesulfonyloxyphenyl)butanoic acidmethyl ester, N-benzyl-3-amino-4-(4-benzenesulfonyloxyphenyl)butanoicacid ethyl ester,N-benzyl-3-amino-4-(4-benzenesulfonyloxyphenyl)butanoic acid isopropylester, N-benzyl-3-amino-4-(4-benzenesulfonyloxyphenyl)butanoic acidt-butyl ester, N-benzyl-3-amino-4-(4-benzenesulfonyloxyphenyl)butanoicacid benzyl ester,

[0283]N-(9-fluorenylmethoxycarbonyl)-3-amino-4-(4-(p-toluenesulfonyloxy)phenyl)butanoicacid methyl ester,N-(9-fluorenylmethoxycarbonyl)-3-amino-4-(4-(p-toluenesulfonyloxy)phenyl)butanoicacid ethyl ester,N-(9-fluorenylmethoxycarbonyl)-3-amino-4-(4-(p-toluenesulfonyloxy)phenyl)butanoicacid isopropyl ester,N-(9-fluorenylmethoxycarbonyl)-3-amino-4-(4-(p-toluenesulfonyloxy)phenyl)butanoicacid t-butyl ester,N-(9-fluorenylmethoxycarbonyl)-3-amino-4-(4-(p-toluenesulfonyloxy)phenyl)butanoicacid benzyl ester,N-(9-fluorenylmethoxycarbonyl)-3-amino-4-(4-methanesulfonyloxyphenyl)butanoicacid methyl ester,N-(9-fluorenylmethoxycarbonyl)-3-amino-4-(4-methanesulfonyloxyphenyl)butanoicacid ethyl ester,N-(9-fluorenylmethoxycarbonyl)-3-amino-4-(4-methanesulfonyloxyphenyl)butanoicacid isopropyl ester,N-(9-fluorenylmethoxycarbonyl)-3-amino-4-(4-methanesulfonyloxyphenyl)butanoicacid t-butyl ester,N-(9-fluorenylmethoxycarbonyl)-3-amino-4-(4-methanesulfonyloxyphenyl)butanoicacid benzyl ester,N-(9-fluorenylmethoxycarbonyl)-3-amino-4-(4-benzenesulfonyloxyphenyl)butanoicacid methyl ester,N-(9-fluorenylmethoxycarbonyl)-3-amino-4-(4-benzenesulfonyloxyphenyl)butanoicacid ethyl ester,N-(9-fluorenylmethoxycarbonyl)-3-amino-4-(4-benzenesulfonyloxyphenyl)butanoicacid isopropyl ester,N-(9-fluorenylmethoxycarbonyl)-3-amino-4-(4-benzenesulfonyloxyphenyl)butanoicacid t-butyl ester,N-(9-fluorenylmethoxycarbonyl)-3-amino-4-(4-benzenesulfonyloxyphenyl)butanoicacid benzyl ester,

[0284]N-benzyloxycarbonyl-3-amino-4-(4-(p-toluenesulfonyloxy)phenyl)butanoicacid methyl ester,N-benzyloxycarbonyl-3-amino-4-(4-(p-toluenesulfonyloxy)phenyl)butanoicacid ethyl ester,N-benzyloxycarbonyl-3-amino-4-(4-(p-toluenesulfonyloxy)phenyl)butanoicacid isopropyl ester,N-benzyloxycarbonyl-3-amino-4-(4-(p-toluenesulfonyloxy)phenyl)butanoicacid t-butyl ester,N-benzyloxycarbonyl-3-amino-4-(4-(p-toluenesulfonyloxy)phenyl)butanoicacid benzyl ester,N-benzyloxycarbonyl-3-amino-4-(4-methanesulfonyloxyphenyl)butanoic acidmethyl ester,N-benzyloxycarbonyl-3-amino-4-(4-methanesulfonyloxyphenyl)butanoic acidethyl ester,N-benzyloxycarbonyl-3-amino-4-(4-methanesulfonyloxyphenyl)butanoic acidisopropyl ester,N-benzyloxycarbonyl-3-amino-4-(4-methanesulfonyloxyphenyl)butanoic acidt-butyl ester,N-benzyloxycarbonyl-3-amino-4-(4-methanesulfonyloxyphenyl)butanoic acidbenzyl ester,N-benzyloxycarbonyl-3-amino-4-(4-benzenesulfonyloxyphenyl)butanoic acidmethyl ester,N-benzyloxycarbonyl-3-amino-4-(4-benzenesulfonyloxyphenyl)butanoic acidethyl ester,N-benzyloxycarbonyl-3-amino-4-(4-benzenesulfonyloxyphenyl)butanoic acidisopropyl ester,N-benzyloxycarbonyl-3-amino-4-(4-benzenesulfonyloxyphenyl)butanoic acidt-butyl ester,N-benzyloxycarbonyl-3-amino-4-(4-benzenesulfonyloxyphenyl)butanoic acidbenzyl ester,

[0285]N-(t-butyloxycarbonyl)-2-aminomethyl-3-(4-(p-toluenesulfonyloxy)phenyl)propanoicacid methyl ester,N-(t-butyloxycarbonyl)-2-aminomethyl-3-(4-(p-toluenesulfonyloxy)phenyl)propanoicacid ethyl ester,N-(t-butyloxycarbonyl)-2-aminomethyl-3-(4-(p-toluenesulfonyloxy)phenyl)propanoicacid isopropyl ester,

[0286]N-(t-butyloxycarbonyl)-2-aminomethyl-3-(4-(p-toluenesulfonyloxy)phenyl)propanoicacid t-butyl ester,N-(t-butyloxycarbonyl)-2-aminomethyl-3-(4-(p-toluenesulfonyloxy)phenyl)propanoicacid benzyl ester,N-(t-butyloxycarbonyl)-2-aminomethyl-3-(4-methanesulfonyloxyphenyl)propanoicacid methyl ester,N-(t-butyloxycarbonyl)-2-aminomethyl-3-(4-methanesulfonyloxyphenyl)propanoicacid ethyl ester,N-(t-butyloxycarbonyl)-2-aminomethyl-3-(4-methanesulfonyloxyphenyl)propanoicacid isopropyl ester,N-(t-butyloxycarbonyl)-2-aminomethyl-3-(4-methanesulfonyloxyphenyl)propanoicacid t-butyl ester,N-(t-butyloxycarbonyl)-2-aminomethyl-3-(4-methanesulfonyloxyphenyl)propanoicacid benzyl ester,N-(t-butyloxycarbonyl)-2-aminomethyl-3-(4-benzenesulfonyloxyphenyl)propanoicacid methyl ester,N-(t-butyloxycarbonyl)-2-aminomethyl-3-(4-benzenesulfonyloxyphenyl)propanoicacid ethyl ester,N-(t-butyloxycarbonyl)-2-aminomethyl-3-(4-benzenesulfonyloxyphenyl)propanoicacid isopropyl ester,N-(t-butyloxycarbonyl)-2-aminomethyl-3-(4-benzenesulfonyloxyphenyl)propanoicacid t-butyl ester,N-(t-butyloxycarbonyl)-2-aminomethyl-3-(4-benzenesulfonyloxyphenyl)propanoicacid benzyl ester,

[0287]N-acetyl-2-aminomethyl-3-(4-(p-toluenesulfonyloxy)phenyl)propanoic acidmethyl ester,N-acetyl-2-aminomethyl-3-(4-(p-toluenesulfonyloxy)phenyl)propanoic acidethyl ester, N-2-aminomethyl-3-(4-(p-toluenesulfonyloxy)phenyl)propanoicacid isopropyl ester,N-2-aminomethyl-3-(4-(p-toluenesulfonyloxy)phenyl)propanoic acid t-butylester,N-acetyl-2-aminomethyl-3-(4-(p-toluenesulfonyloxy)phenyl)propanoic acidbenzyl ester,N-acetyl-2-aminomethyl-3-(4-methanesulfonyloxyphenyl)propanoic acidmethyl ester,N-acetyl-2-aminomethyl-3-(4-methanesulfonyloxyphenyl)propanoic acidethyl ester,N-acetyl-2-aminomethyl-3-(4-methanesulfonyloxyphenyl)propanoic acidisopropyl ester,N-acetyl-2-aminomethyl-3-(4-methanesulfonyloxyphenyl)propanoic acidt-butyl ester,N-acetyl-2-aminomethyl-3-(4-methanesulfonyloxyphenyl)propanoic acidbenzyl ester,N-acetyl-2-aminomethyl-3-(4-benzenesulfonyloxyphenyl)propanoic acidmethyl ester,N-acetyl-2-aminomethyl-3-(4-benzenesulfonyloxyphenyl)propanoic acidethyl ester,N-acetyl-2-aminomethyl-3-(4-benzenesulfonyloxyphenyl)propanoic acidisopropyl ester,N-acetyl-2-aminomethyl-3-(4-benzenesulfonyloxyphenyl)propanoic acidt-butyl ester,N-acetyl-2-aminomethyl-3-(4-benzenesulfonyloxyphenyl)propanoic acidbenzyl ester,

[0288]N-benzyl-2-aminomethyl-3-(4-(p-toluenesulfonyloxy)phenyl)propanoic acidmethyl ester,N-benzyl-2-aminomethyl-3-(4-(p-toluenesulfonyloxy)phenyl)propanoic acidethyl ester,N-benzyl-2-aminomethyl-3-(4-(p-toluenesulfonyloxy)phenyl)propanoic acidisopropyl ester,

[0289]N-benzyl-2-aminomethyl-3-(4-(p-toluenesulfonyloxy)phenyl)propanoic acidt-butyl ester,N-benzyl-2-aminomethyl-3-(4-(p-toluenesulfonyloxy)phenyl)propanoic acidbenzyl ester,N-benzyl-2-aminomethyl-3-(4-methanesulfonyloxyphenyl)propanoic acidmethyl ester,N-benzyl-2-aminomethyl-3-(4-methanesulfonyloxyphenyl)propanoic acidethyl ester,N-benzyl-2-aminomethyl-3-(4-methanesulfonyloxyphenyl)propanoic acidisopropyl ester,N-benzyl-2-aminomethyl-3-(4-methanesulfonyloxyphenyl)propanoic acidt-butyl ester,N-benzyl-2-aminomethyl-3-(4-methanesulfonyloxyphenyl)propanoic acidbenzyl ester,N-benzyl-2-aminomethyl-3-(4-benzenesulfonyloxyphenyl)propanoic acidmethyl ester,N-benzyl-2-aminomethyl-3-(4-benzenesulfonyloxyphenyl)propanoic acidethyl ester,N-benzyl-2-aminomethyl-3-(4-benzenesulfonyloxyphenyl)propanoic acidisopropyl ester,N-benzyl-2-aminomethyl-3-(4-benzenesulfonyloxyphenyl)propanoic acidt-butyl ester,N-benzyl-2-aminomethyl-3-(4-benzenesulfonyloxyphenyl)propanoic acidbenzyl ester,

[0290]N-(9-fluorenylmethoxycarbonyl)-2-aminomethyl-3-(4-(p-toluenesulfonyloxy)phenyl)propanoicacid methyl ester,N-(9-fluorenylmethoxycarbonyl)-2-aminomethyl-3-(4-(p-toluenesulfonyloxy)phenyl)propanoicacid ethyl ester,N-(9-fluorenylmethoxycarbonyl)-2-aminomethyl-3-(4-(p-toluenesulfonyloxy)phenyl)propanoicacid isopropyl ester,

[0291]N-(9-fluorenylmethoxycarbonyl)-2-aminomethyl-3-(4-(p-toluenesulfonyloxy)phenyl)propanoicacid t-butyl ester,N-(9-fluorenylmethoxycarbonyl)-2-aminomethyl-3-(4-(p-toluenesulfonyloxy)phenyl)propanoicacid benzyl ester,N-(9-fluorenylmethoxycarbonyl)-2-aminomethyl-3-(4-methanesulfonyloxyphenyl)propanoicacid methyl ester,N-(9-fluorenylmethoxycarbonyl)-2-aminomethyl-3-(4-methanesulfonyloxyphenyl)propanoicacid ethyl ester,N-(9-fluorenylmethoxycarbonyl)-2-aminomethyl-3-(4-methanesulfonyloxyphenyl)propanoicacid isopropyl ester,N-(9-fluorenylmethoxycarbonyl)-2-aminomethyl-3-(4-methanesulfonyloxyphenyl)propanoicacid t-butyl ester,N-(9-fluorenylmethoxycarbonyl)-2-aminomethyl-3-(4-methanesulfonyloxyphenyl)propanoicacid benzyl ester,N-(9-fluorenylmethoxycarbonyl)-2-aminomethyl-3-(4-benzenesulfonyloxyphenyl)propanoicacid methyl ester,N-(9-fluorenylmethoxycarbonyl)-2-aminomethyl-3-(4-benzenesulfonyloxyphenyl)propanoicacid ethyl ester,N-(9-fluorenylmethoxycarbonyl)-2-aminomethyl-3-(4-benzenesulfonyloxyphenyl)propanoicacid isopropyl ester,N-(9-fluorenylmethoxycarbonyl)-2-aminomethyl-3-(4-benzenesulfonyloxyphenyl)propanoicacid t-butyl ester,N-(9-fluorenylmethoxycarbonyl)-2-aminomethyl-3-(4-benzenesulfonyloxyphenyl)propanoicacid benzyl ester,

[0292]N-benzyloxycarbonyl-2-aminomethyl-3-(4-(p-toluenesulfonyloxy)phenyl)propanoicacid methyl ester,N-benzyloxycarbonyl-2-aminomethyl-3-(4-(p-toluenesulfonyloxy)phenyl)propanoicacid ethyl ester,N-benzyloxycarbonyl-2-aminomethyl-3-(4-(p-toluenesulfonyloxy)phenyl)propanoicacid isopropyl ester,

[0293]N-benzyloxycarbonyl-2-aminomethyl-3-(4-(p-toluenesulfonyloxy)phenyl)propanoicacid t-butyl ester,N-benzyloxycarbonyl-2-aminomethyl-3-(4-(p-toluenesulfonyloxy)phenyl)propanoicacid benzyl ester,N-benzyloxycarbonyl-2-aminomethyl-3-(4-methanesulfonyloxyphenyl)propanoicacid methyl ester,N-benzyloxycarbonyl-2-aminomethyl-3-(4-methanesulfonyloxyphenyl)propanoicacid ethyl ester,N-benzyloxycarbonyl-2-aminomethyl-3-(4-methanesulfonyloxyphenyl)propanoicacid isopropyl ester,N-benzyloxycarbonyl-2-aminomethyl-3-(4-methanesulfonyloxyphenyl)propanoicacid t-butyl ester,N-benzyloxycarbonyl-2-aminomethyl-3-(4-methanesulfonyloxyphenyl)propanoicacid benzyl ester,N-benzyloxycarbonyl-2-aminomethyl-3-(4-benzenesulfonyloxyphenyl)propanoicacid methyl ester,N-benzyloxycarbonyl-2-aminomethyl-3-(4-benzenesulfonyloxyphenyl)propanoicacid ethyl ester,N-benzyloxycarbonyl-2-aminomethyl-3-(4-benzenesulfonyloxyphenyl)propanoicacid isopropyl ester,N-benzyloxycarbonyl-2-aminomethyl-3-(4-benzenesulfonyloxyphenyl)propanoicacid t-butyl ester,N-benzyloxycarbonyl-2-aminomethyl-3-(4-benzenesulfonyloxyphenyl)propanoicacid benzyl ester,

[0294]N-(t-butyloxycarbonyl)-3-aminomethyl-4-(4-(p-toluenesulfonyloxy)phenyl)butanoicacid methyl ester,N-(t-butyloxycarbonyl)-3-aminomethyl-4-(4-(p-toluenesulfonyloxy)phenyl)butanoicacid ethyl ester,N-(t-butyloxycarbonyl)-3-aminomethyl-4-(4-(p-toluenesulfonyloxy)phenyl)butanoicacid isopropyl ester,N-(t-butyloxycarbonyl)-3-aminomethyl-4-(4-(p-toluenesulfonyloxy)phenyl)butanoicacid t-butyl ester,N-(t-butyloxycarbonyl)-3-aminomethyl-4-(4-(p-toluenesulfonyloxy)phenyl)butanoicacid benzyl ester,N-(t-butyloxycarbonyl)-3-aminomethyl-4-(4-methanesulfonyloxyphenyl)butanoicacid methyl ester,N-(t-butyloxycarbonyl)-3-aminomethyl-4-(4-methanesulfonyloxyphenyl)butanoicacid ethyl ester,N-(t-butyloxycarbonyl)-3-aminomethyl-4-(4-methanesulfonyloxyphenyl)butanoicacid isopropyl ester,N-(t-butyloxycarbonyl)-3-aminomethyl-4-(4-methanesulfonyloxyphenyl)butanoicacid t-butyl ester,N-(t-butyloxycarbonyl)-3-aminomethyl-4-(4-methanesulfonyloxyphenyl)butanoicacid benzyl ester,N-(t-butyloxycarbonyl)-3-aminomethyl-4-(4-benzenesulfonyloxyphenyl)butanoicacid methyl ester,N-(t-butyloxycarbonyl)-3-aminomethyl-4-(4-benzenesulfonyloxyphenyl)butanoicacid ethyl ester,N-(t-butyloxycarbonyl)-3-aminomethyl-4-(4-benzenesulfonyloxyphenyl)butanoicacid isopropyl ester,N-(t-butyloxycarbonyl)-3-aminomethyl-4-(4-benzenesulfonyloxyphenyl)butanoicacid t-butyl ester,N-(t-butyloxycarbonyl)-3-aminomethyl-4-(4-benzenesulfonyloxyphenyl)butanoicacid benzyl ester,

[0295] N-acetyl-3-aminomethyl-4-(4-(p-toluenesulfonyloxy)phenyl)butanoicacid methyl ester,N-acetyl-3-aminomethyl-4-(4-(p-toluenesulfonyloxy)phenyl)butanoic acidethyl ester, N-3-aminomethyl-4-(4-(p-toluenesulfonyloxy)phenyl)butanoicacid isopropyl ester,N-3-aminomethyl-4-(4-(p-toluenesulfonyloxy)phenyl)butanoic acid t-butylester, N-acetyl-3-aminomethyl-4-(4-(p-toluenesulfonyloxy)phenyl)butanoicacid benzyl ester,N-acetyl-3-aminomethyl-4-(4-methanesulfonyloxyphenyl)butanoic acidmethyl ester,N-acetyl-3-aminomethyl-4-(4-methanesulfonyloxyphenyl)butanoic acid ethylester, N-acetyl-3-aminomethyl-4-(4-methanesulfonyloxyphenyl)butanoicacid isopropyl ester,N-acetyl-3-aminomethyl-4-(4-methanesulfonyloxyphenyl)butanoic acidt-butyl ester,N-acetyl-3-aminomethyl-4-(4-methanesulfonyloxyphenyl)butanoic acidbenzyl ester,N-acetyl-3-aminomethyl-4-(4-benzenesulfonyloxyphenyl)butanoic acidmethyl ester,N-acetyl-3-aminomethyl-4-(4-benzenesulfonyloxyphenyl)butanoic acid ethylester, N-acetyl-3-aminomethyl-4-(4-benzenesulfonyloxyphenyl)butanoicacid isopropyl ester,N-acetyl-3-aminomethyl-4-(4-benzenesulfonyloxyphenyl)butanoic acidt-butyl ester,N-acetyl-3-aminomethyl-4-(4-benzenesulfonyloxyphenyl)butanoic acidbenzyl ester,

[0296] N-benzyl-3-aminomethyl-4-(4-(p-toluenesulfonyloxy)phenyl)butanoicacid methyl ester,N-benzyl-3-aminomethyl-4-(4-(p-toluenesulfonyloxy)phenyl)butanoic acidethyl ester,N-benzyl-3-aminomethyl-4-(4-(p-toluenesulfonyloxy)phenyl)butanoic acidisopropyl ester,N-benzyl-3-aminomethyl-4-(4-(p-toluenesulfonyloxy)phenyl)butanoic acidt-butyl ester,N-benzyl-3-aminomethyl-4-(4-(p-toluenesulfonyloxy)phenyl)butanoic acidbenzyl ester,N-benzyl-3-aminomethyl-4-(4-methanesulfonyloxyphenyl)butanoic acidmethyl ester,N-benzyl-3-aminomethyl-4-(4-methanesulfonyloxyphenyl)butanoic acid ethylester, N-benzyl-3-aminomethyl-4-(4-methanesulfonyloxyphenyl)butanoicacid isopropyl ester,N-benzyl-3-aminomethyl-4-(4-methanesulfonyloxyphenyl)butanoic acidt-butyl ester,N-benzyl-3-aminomethyl-4-(4-methanesulfonyloxyphenyl)butanoic acidbenzyl ester,N-benzyl-3-aminomethyl-4-(4-benzenesulfonyloxyphenyl)butanoic acidmethyl ester,N-benzyl-3-aminomethyl-4-(4-benzenesulfonyloxyphenyl)butanoic acid ethylester, N-benzyl-3-aminomethyl-4-(4-benzenesulfonyloxyphenyl)butanoicacid isopropyl ester,N-benzyl-3-aminomethyl-4-(4-benzenesulfonyloxyphenyl)butanoic acidt-butyl ester,N-benzyl-3-aminomethyl-4-(4-benzenesulfonyloxyphenyl)butanoic acidbenzyl ester,

[0297]N-(9-fluorenylmethoxycarbonyl)-3-aminomethyl-4-(4-(p-toluenesulfonyloxy)phenyl)butanoicacid methyl ester,N-(9-fluorenylmethoxycarbonyl)-3-aminomethyl-4-(4-(p-toluenesulfonyloxy)phenyl)butanoicacid ethyl ester,N-(9-fluorenylmethoxycarbonyl)-3-aminomethyl-4-(4-(p-toluenesulfonyloxy)phenyl)butanoicacid isopropyl ester,N-(9-fluorenylmethoxycarbonyl)-3-aminomethyl-4-(4-(p-toluenesulfonyloxy)phenyl)butanoicacid t-butyl ester,N-(9-fluorenylmethoxycarbonyl)-3-aminomethyl-4-(4-(p-toluenesulfonyloxy)phenyl)butanoicacid benzyl ester,N-(9-fluorenylmethoxycarbonyl)-3-aminomethyl-4-(4-methanesulfonyloxyphenyl)butanoicacid methyl ester,N-(9-fluorenylmethoxycarbonyl)-3-aminomethyl-4-(4-methanesulfonyloxyphenyl)butanoicacid ethyl ester,N-(9-fluorenylmethoxycarbonyl)-3-aminomethyl-4-(4-methanesulfonyloxyphenyl)butanoicacid isopropyl ester,N-(9-fluorenylmethoxycarbonyl)-3-aminomethyl-4-(4-methanesulfonyloxyphenyl)butanoicacid t-butyl ester,N-(9-fluorenylmethoxycarbonyl)-3-aminomethyl-4-(4-methanesulfonyloxyphenyl)butanoicacid benzyl ester,N-(9-fluorenylmethoxycarbonyl)-3-aminomethyl-4-(4-benzenesulfonyloxyphenyl)butanoicacid methyl ester,N-(9-fluorenylmethoxycarbonyl)-3-aminomethyl-4-(4-benzenesulfonyloxyphenyl)butanoicacid ethyl ester,N-(9-fluorenylmethoxycarbonyl)-3-aminomethyl-4-(4-benzenesulfonyloxyphenyl)butanoicacid isopropyl ester,N-(9-fluorenylmethoxycarbonyl)-3-aminomethyl-4-(4-benzenesulfonyloxyphenyl)butanoicacid t-butyl ester,N-(9-fluorenylmethoxycarbonyl)-3-aminomethyl-4-(4-benzenesulfonyloxyphenyl)butanoicacid benzyl ester,

[0298]N-benzyloxycarbonyl-3-aminomethyl-4-(4-(p-toluenesulfonyloxy)phenyl)butanoicacid methyl ester,N-benzyloxycarbonyl-3-aminomethyl-4-(4-(p-toluenesulfonyloxy)phenyl)butanoicacid ethyl ester,N-benzyloxycarbonyl-3-aminomethyl-4-(4-(p-toluenesulfonyloxy)phenyl)butanoicacid isopropyl ester,N-benzyloxycarbonyl-3-aminomethyl-4-(4-(p-toluenesulfonyloxy)phenyl)butanoicacid t-butyl ester,N-benzyloxycarbonyl-3-aminomethyl-4-(4-(p-toluenesulfonyloxy)phenyl)butanoicacid benzyl ester,N-benzyloxycarbonyl-3-aminomethyl-4-(4-methanesulfonyloxyphenyl)butanoicacid methyl ester,N-benzyloxycarbonyl-3-aminomethyl-4-(4-methanesulfonyloxyphenyl)butanoicacid ethyl ester,N-benzyloxycarbonyl-3-aminomethyl-4-(4-methanesulfonyloxyphenyl)butanoicacid isopropyl ester,N-benzyloxycarbonyl-3-aminomethyl-4-(4-methanesulfonyloxyphenyl)butanoicacid t-butyl ester,N-benzyloxycarbonyl-3-aminomethyl-4-(4-methanesulfonyloxyphenyl)butanoicacid benzyl ester,N-benzyloxycarbonyl-3-aminomethyl-4-(4-benzenesulfonyloxyphenyl)butanoicacid methyl ester,N-benzyloxycarbonyl-3-aminomethyl-4-(4-benzenesulfonyloxyphenyl)butanoicacid ethyl ester,N-benzyloxycarbonyl-3-aminomethyl-4-(4-benzenesulfonyloxyphenyl)butanoicacid isopropyl ester,N-benzyloxycarbonyl-3-aminomethyl-4-(4-benzenesulfonyloxyphenyl)butanoicacid t-butyl ester,N-benzyloxycarbonyl-3-aminomethyl-4-(4-benzenesulfonyloxyphenyl)butanoicacid benzyl ester, etc.

[0299] Furthermore, the above-mentioned compounds wherein the hydrogenon the aromatic ring is substituted with a fluorine atom, an alkylgroup, a cycloalkyl group, a hydroxyl group, an alkoxyl group, anaryloxy group, an alkylthio group, an arylthio group, a cyano group, anitro group, a protected amino group, a substituted or unsubstitutedsulfonamide group, a formyl group, a carboxyl group, an alkylcarbonylgroup, an arylcarbonyl group, an alkoxycarbonyl group, anaryloxycarbonyl group, a substituted or unsubstituted carbamoyl group, asubstituted or unsubstituted heterocyclic group, or a substituted orunsubstituted aryl group as mentioned above, are included.

[0300] The unsubstituted aryl group represented by R³ in the organicboron compound (2) and boroxine ring compound (3) includes, but notspecifically limited to, a monocyclic to tricyclic aryl group consistingof 6 to 14 carbon atoms. Examples of such aryl group include a phenylgroup, a naphthyl group, an anthracenyl group, a phenanthryl group, anindenyl group and a fluorenyl group. Furthermore, the unsubstitutedheteroaryl group represented by R³ includes, but not specificallylimited to, a 5- to 7-membered aromatic heterocyclic group containing 1to 3 heteroatoms selected from 0 to 3 nitrogen atoms, 0 to 2 oxygenatoms and 0 to 2 sulfur atoms. Examples of such heteroaryl group includea pyridyl group, a furyl group, a thienyl group, a pyrrolyl group andimidazolyl group.

[0301] The substituents for the substituted aryl group or substitutedheteroaryl group represented by R³ include one or more identical ordifferent substituents. Specific examples thereof include a fluorineatom; substituted or unsubstituted alkyl groups such as a methyl group,an ethyl group, an i-propyl group, a trifluoromethyl group, a cycloalkylgroup or alkylaminoalkyl groups such as a dimethylaminomethyl group;protected hydroxyl groups; alkoxy groups such as a methoxy group, anethoxy group or a t-butoxy group; a phenoxy group; alkylthio groups suchas a methylthio group; arylthio groups such as a phenylthio group; acyano group; a nitro group; alkyl-substituted amino groups such as adimethylamino group or a cyclohexylamino group; acylamino groups such asa t-butoxycarbonylamino group or an acetoxyamino group; protected aminogroups such as imide groups such as a phthalimide group; sulfonamidegroups such as a benzenesulfonamide group or a methanesulfonamide group;a imino group; a formyl group; a carboxyl group; substituted orunsubstituted alkoxycarbonyl groups such as a methoxycarboxyl group;substituted or unsubstituted aryloxycarbonyl groups such as ap-methoxyphenoxycarbonyl group; unsubstituted or substituted carbamoylgroups such as a carbamoyl group or a N-phenylcarbamoyl group;substituted or unsubstituted heterocyclic groups such as a pyridylgroup, a furyl group or thienyl group; and substituted or unsubstitutedaryl groups such as a phenyl group or a naphthyl group. Of thesesubstituents, two substituents on the adjacent carbon atoms may be boundeach other and taken together with R³ to form a fused ring.

[0302] Specific examples of the organic boron compound of the formula(2) of the present invention include phenylboronic acid,2-methylphenylboronic acid, 3-methylphenylboronic acid,4-methylphenylboronic acid, 2,3-dimethylphenylboronic acid,2,4-dimethylphenylboronic acid, 2,5-dimethylphenylboronic acid,2,6-dimethylphenylboronic acid, 2,4,6-trimethylphenylboronic acid,2,3,5,6-tetramethylphenylboronic acid, 2-ethylphenylboronic acid,4-n-propylphenylboronic acid, 4-isopropylphenylboronic acid,4-n-butylphenylboronic acid, 4-t-butylphenylboronic acid,1-naphthylboronic acid, 2-naphthylboronic acid, 2-biphenylboronic acid,3-biphenylboronic acid, 4-biphenylboronic acid,2-fluoro-4-biphenylboronic acid, 2-fluorenylboronic acid,9-fluorenylboronic acid, 9-phenanthrenylboronic acid,9-anthracenylboronic acid, 1-pyrenylboronic acid,2-trifluoromethylphenylboronic acid, 3-trifluoromethylphenylboronicacid, 4-trifluorophenylboronic acid,3,5-bis(trifluoromethyl)phenylboronic acid, 2-methoxyphenylboronic acid,3-methoxyphenylboronic acid, 4-methoxyphenylboronic acid,2,5-dimethoxyphenylboronic acid, 2,6-dimethoxyphenylboronic acid,4,5-dimethoxyphenylboronic acid, 2,4-dimethoxyphenylboronic acid,2-ethoxyphenylboronic acid, 3-ethoxyphenylboronic acid,4-ethoxyphenylboronic acid, 4-phenoxyboronic acid,3,4-methylenedioxyphenylboronic acid, 2-fluorophenylboronic acid,3-fluorophenylboronic acid, 4-fluorophenylboronic acid,2,4-difluorophenylboronic acid, 2,5-difluorophenylboronic acid,2,6-difluorophenylboronic acid, 4,5-difluorophenylboronic acid,3,5-difluorophenylboronic acid, 2-formylphenylboronic acid,3-formylphenylboronic acid, 4-formylphenylboronic acid,3-formyl-4-methoxyphenylboronic acid, 2-cyanophenylboronic acid,3-cyanophenylboronic acid, 4-cyanophenylboronic acid,3-nitrophenylboronic acid, 3-acetylphenylboronic acid,4-acetylphenylboronic acid, 3-trifluoroacetylphenylboronic acid,4-trifluoroacetylphenylboronic acid, 4-methylthiophenylboronic acid,4-vinylphenylboronic acid, 3-carboxyphenylboronic acid,4-carboxyphenylboronic acid, 3-aminophenylboronic acid,2-(N,N-dimethylamino)phenylboronic acid,3-(N,N-dimethylamino)phenylboronic acid,4-(N,N-dimethylamino)phenylboronic acid,2-(N,N-diethylamino)phenylboronic acid,3-(N,N-diethylamino)phenylboronic acid,4-(N,N-diethylamino)phenylboronic acid,2-(N,N-dimethylaminomethyl)phenylboronic acid, furan-2-boronic acid,furan-3-boronic acid, 2-formylfuranboronic acid, 3-formylfuran-2-boronicacid, dibenzofuran-4-boronic acid, benzofuran-2-boronic acid,thiophene-2-boronic acid, thiophene-3-boronic acid,5-methylthiophene-2-boronic acid, 5-chlorothiophene-2-boronic acid,4-methylthiophene-2-boronic acid, 5-methylthiophene-2-boronic acid,2-acetylthiophene-5-boronic acid, 3-formylthiophene-2-boronic acid,5-methylthiophene-2-boronic acid, benzothiophene-2-boronic acid,dibenzothiophene-4-boronic acid, pyrazole-4-boronic acid,3-methylpyrazole-4-boronic acid, 3,5-dimethylpyrazole-4-boronic acid,3-nitro-1,2,4-triazole-5-boronic acid, thiazole-2-boronic acid,pyridine-3-boronic acid, pyridine-4-boronic acid, pyrimidine-5-boronicacid, quinoline-8-boronic acid, isoquinoline-4-boronic acid,1,4-benzenebis(boronic acid), and pinacol esters and catechol esters ofthese boronic acids.

[0303] In the reaction, the amount used of the organic boron compound ofthe formula (2) is usually from 1 mol to 10 mol, preferably not morethan 3 mol, relative to 1 mol of the aromatic sulfonic acid estercompound of the formula (1).

[0304] The nickel catalyst used may be zerovalent or divalent.Alternatively, a divalent nickel catalyst may be previously reduced tozerovalence by using a reducing agent before use. The zerovalentcatalyst includes bis(1,5-cyclooctadiene)nickel(0) andtetrakis(triphenylphosphine)nickel(0). The divalent catalyst includesnickel halide metal compounds (II) such as nickel(II) chloride,nickel(II) bromide and nickel(II) iodide, nickel(II) nitrate, nickel(II)acetate, bis(triphenylphosphine)nickel(II) dichloride, and nickel(II)bisacetylacetonate. These nickel catalysts may optionally contain aligand. Alternatively, a ligand may be added to the reaction mixtureindependently. Such a ligand includes phosphorus-containing compounds,for example, triarylphosphines such as triphenylphosphine,trialkylphosphines such as tricyclohexylphosphine ortri-t-butylphosphine, bis(diphenylphosphino)ferrocene, etc.

[0305] The reducing agent used for previously reducing the divalentnickel to zerovalence includes, but not limited to, sodium borohydride,lithium aluminum hydride, sodium hydride, di-isobutylaluminum hydride,alkyl Grignard's reagents, alkyl lithiums, alkyl aluminums, and zincmetals. In this case, a divalent nickel catalyst, a ligand, a reducingagent and optionally a suitable solvent that does not react with thereducing agent are mixed to prepare a catalyst, but order thereof is notspecifically limited.

[0306] The nickel catalyst may be completely dissolved or suspended inthe reaction mixture. The nickel catalyst may be used directly, or maybe carried by a substance that does not dissolve in a solvent used inthe reaction, such as carbon, silica or alumina.

[0307] In the reaction, the amount used of the nickel catalyst isusually from 0.00001 mol to 1 mol, preferably not more than 0.2 mol,relative to 1 mol of the aromatic sulfonic acid ester compound of theformula (1). The amount used of the ligand is usually from 0.1 mol to 10mol, preferably from 0.5 mol to 5 mol relative to 1 mol of the nickelcatalyst.

[0308] In the present invention, a base is usually used. Such a baseincludes hydroxide, carbonate, phosphate, carboxylate and alkoxide of analkali metal or alkaline earth metal, and alkali metal hydrogencarbonateand alkali metal fluoride. Such salts of alkali metal and alkaline earthmetal include inorganic bases such as lithium carbonate, sodiumcarbonate, potassium carbonate, cesium carbonate, calcium carbonate,barium carbonate, lithium phosphate, sodium phosphate and potassiumphosphate, preferably cesium carbonate. The base further includestertiary amine compounds such as trimethylamine, triethylamine,N,N-dimethylbenzylamine and N,N-diethylaniline.

[0309] The amount used of the base is usually from 0.1 to 20 mol,preferably 1 to 5 mol, relative to 1 mol of the aromatic sulfonic acidester compound of the formula (1). Furthermore, two or more of the basesmay be used in combination.

[0310] In the reaction, a solvent is usually used. Organic solvents,water, or mixtures thereof may be used as a solvent.

[0311] The organic solvent includes alcohol solvents such as methanoland ethanol, aprotic solvents such as N-methylpyrrolidone,N,N-dimethylformamide, dimethylsulfoxide and acetonitrile, ethersolvents such as diethyl ether, di-isopropyl ether, diethylene glycoldimethyl ether, 1,4-dioxane and tetrahydrofuran, aromatic hydrocarbonssuch as benzene, toluene and xylene, aliphatic hydrocarbons such ashexane and heptane. These solvents may be used alone or in a combinationof two or more. The amount used of the solvent is usually from 0.5 to200 parts by weight, preferably from 1 to 10 parts by weight, relativeto 1 part by weight of the aromatic sulfonic acid ester compound of theformula (1).

[0312] In the preparation process of the present invention, the aromaticsulfonic acid ester compound of formula (1), organic boron compound ofthe formula (2), nickel catalyst, ligand, base and, if necessary, asolvent may be mixed in any order. However, in the case wherein areducing agent is used and the agent may react with the aromatic aminoacid derivative or organic boron compound, it is preferable that theabove materials are added in the order whereby the reaction of thereducing agent with the aromatic amino acid derivative or organic boroncompound can be avoided. For example, it is preferable that an aromaticamino acid derivative, an organic boron compound, a base and optionallya suitable solvent are mixed previously in any order and then to themixture, a mixture prepared from a nickel catalyst, a ligand and areducing agent is added; or to a mixture prepared from a nickelcatalyst, a ligand and a reducing agent, an aromatic amino acidderivative, an organic boron compound, a base and optionally a suitablesolvent are added in any order. In addition, in this case, a compound inwhich a ligand is coordinated to a nickel catalyst may be used insteadof a ligand and a nickel catalyst.

[0313] The reaction temperature is usually 70° C. or below, preferablyin the range of room temperature to 50° C.

[0314] After the reaction, insoluble substances in the system areremoved by filtration etc., if necessary, and a usual post-treatment iscarried out to give the desired optically active biaryl compound of thefollowing formula (4):

[0315] wherein R*, R², R³, n₁, n₂ and * are as defined hereinabove, withfine optical purity.

[0316] Particularly, when the optically active amino acid compound ofthe formula (1a) is used as a starting compound, the optically activebiaryl amino acid compound of the following formula (4a):

[0317] wherein R³, R¹¹, R¹², R¹³, n₁₁, n₁₂, n₁₃ and * are as definedhereinabove, can be obtained with fine optical purity. Not only theoptically active amino acid compounds (1a) and (4a) but alsocompositions comprising the optically active compound of the formula(1a) or (4a) and an enantiomer thereof in any ratio (inclusive of aracemate) can be prepared similarly to the optically active compounds.

EXAMPLES

[0318] The following examples explain the present invention moreparticularly, but they do not limit the present invention.

Example 1

[0319]

[0320] Under a nitrogen atmosphere,(L)-N-(t-butyloxycarbonyl)-O-(p-toluenesulfonyl)tyrosine methyl ester(0.94 g, 2.0 mmol), 2,6-dimethoxyphenylboronic acid (0.55 g, 3.0 mmol),cesium carbonate (1.32 g, 4.0 mmol), tricyclohexylphosphine (0.059 g,0.2 mmol) and bis(1,5-cyclooctadiene)nickel (0.028 g, 0.1 mmol) weremixed in dioxane (2 ml). The reaction mixture was heated to 50° C. andthen stirred at the same temperature for 15 hrs. After the reaction wascompleted, the mixture was left to cool to room temperature andinsoluble substances were filtered off. The filtrate was subjected toliquid chromatography to analyze(L)-N-(t-butyloxycarbonyl)-4-(2,6-dimethoxyphenyl)phenylalanine methylester in the filtrate. As the result, the reaction yield was 100% andthe optical purity of the product was 99.8% ee.

Example 2

[0321] Under a nitrogen atmosphere,(L)-N-(t-butyloxycarbonyl)-O-(p-toluenesulfonyl)tyrosine methyl ester(0.94 g, 2.0 mmol), 2,6-dimethoxyphenylboronic acid (0.55 g, 3.0 mmol),potassium phosphate (0.86 g, 4.1 mmol), tricyclohexylphosphine (0.059 g,0.2 mmol) and bis(1,5-cyclooctadiene)nickel (0.027 g, 0.1 mmol) weremixed in THF (3 ml). The reaction mixture was heated to 50° C. and thenstirred at the same temperature for 15 hrs. After the reaction wascompleted, the mixture was left to cool to room temperature andinsoluble substances were filtered off. The filtrate was subjected toliquid chromatography to analyze(L)-N-(t-butyloxycarbonyl)-4-(2,6-dimethoxyphenyl)phenylalanine methylester in the filtrate. As the result, the reaction yield was 94%.

Example 3

[0322]

[0323] Under a nitrogen atmosphere,(L)-N-(t-butyloxycarbonyl)-O-methanesulfonyltyrosine methyl ester (1.45g, 4.0 mmol), 2,6-dimethoxyphenylboronic acid (1.1 g, 6.0 mmol), cesiumcarbonate (2.6 g, 8.0 mmol), tricyclohexylphosphine (0.12 g, 0.4 mmol)and bis(1,5-cyclooctadiene)nickel (0.055 g, 0.2 mmol) were mixed indioxane (4 ml). The reaction mixture was heated to 50° C. and thenstirred at the same temperature for 5 hrs. After the reaction wascompleted, the mixture was left to cool to room temperature andinsoluble substances were filtered off. The filtrate was subjected toliquid chromatography to analyze(L)-N-(t-butyloxycarbonyl)-4-(2,6-dimethoxyphenyl)phenylalanine methylester in the filtrate. As the result, the reaction yield was 95%.

Example 4

[0324]

[0325] Under a nitrogen atmosphere,(L)-N-(t-butyloxycarbonyl)-O-(p-toluenesulfonyl)tyrosine methyl ester(0.45 g, 1.0 mmol), cesium carbonate (0.65 g, 2.0 mmol),tricyclohexylphosphine (0.059 g, 0.2 mmol) andbis(1,5-cyclooctadiene)nickel (0.028 g, 0.1 mmol) were mixed in dioxane(1 ml) which had been previously mixed with a mixture (0.24 g, 2.0 mmol)of phenylboronic acid and a boroxine ring compound thereof and water(0.03 g). The reaction mixture was heated to 50° C. and then stirred atthe same temperature for 9 hrs. After the reaction was completed, themixture was left to cool to room temperature and insoluble substanceswere filtered off. The filtrate was subjected to column chromatographypurification to obtain (L)-N-(t-butyloxycarbonyl)-4-phenylphenylalaninemethyl ester (0.33 g, yield 95%) as white crystals.

Example 5

[0326]

[0327] Under a nitrogen atmosphere,(L)-N-(t-butyloxycarbonyl)-O-(p-toluenesulfonyl)tyrosine methyl ester(0.45 g, 1.0 mmol), cesium carbonate (0.65 g, 2.0 mmol),tricyclohexylphosphine (0.059 g, 0.2 mmol),bis(1,5-cyclooctadiene)nickel (0.028 g, 0.1 mmol) and2-methoxyphenylboronic acid (0.32 g, 2.0 mmol) were mixed in dioxane (2ml). The reaction mixture was heated to 70° C. and then stirred at thesame temperature for 3 hrs. After the reaction was completed, themixture was left to cool to room temperature and insoluble substanceswere filtered off. The filtrate was subjected to column chromatographypurification to obtain(L)-N-(t-butyloxycarbonyl)-4-(2-methoxyphenyl)phenylalanine methyl ester(0.38 g, yield 98%) as pale yellow oil.

Example 6

[0328]

[0329] Under a nitrogen atmosphere,(L)-N-(t-butyloxycarbonyl)-O-(p-toluenesulfonyl)tyrosine methyl ester(0.45 g, 1.0 mmol), cesium carbonate (0.65 g, 2.0 mmol),tricyclohexylphosphine (0.059 g, 0.2 mmol) andbis(1,5-cyclooctadiene)nickel (0.028 g, 0.1 mmol) were mixed in dioxane(1 ml) which had been previously mixed with a mixture (0.28 g, 2.0 mmol)of 4-methylphenylboronic acid and a boroxine ring compound thereof andwater (0.03 g). The reaction mixture was heated to 70° C. and thenstirred at the same temperature for 3 hrs. After the reaction wascompleted, the mixture was left to cool to room temperature andinsoluble substances were filtered off. The filtrate was subjected tocolumn chromatography purification to obtain(L)-N-(t-butyloxycarbonyl)-4-(4-methylphenyl)phenylalanine methyl ester(0.33 g, yield 89%) as white crystals.

Example 7

[0330]

[0331] Under a nitrogen atmosphere,(L)-N-(t-butyloxycarbonyl)-O-(p-toluenesulfonyl)tyrosine methyl ester(0.45 g, 1.0 mmol), cesium carbonate (0.65 g, 2.0 mmol),tricyclohexylphosphine (0.059 g, 0.2 mmol) andbis(1,5-cyclooctadiene)nickel (0.028 g, 0.1 mmol) were mixed in dioxane(1.25 ml) which had been previously mixed with a mixture (0.34 g, 2.0mmol) of 1-naphthylboronic acid and a boroxine ring compound thereof andwater (0.02 g). The reaction mixture was heated to 70° C. and thenstirred at the same temperature for 4 hrs. After the reaction wascompleted, the mixture was left to cool to room temperature andinsoluble substances were filtered off. The filtrate was subjected tocolumn chromatography purification to obtain(L)-N-(t-butyloxycarbonyl)-4-(1-naphthyl)phenylalanine methyl ester(0.39 g, yield 96%) as white crystals.

Example 8

[0332]

[0333] Under a nitrogen atmosphere,(L)-N-(t-butyloxycarbonyl)-O-(p-toluenesulfonyl)tyrosine methyl ester(0.45 g, 1.0 mmol), cesium carbonate (0.65 g, 2.0 mmol),tricyclohexylphosphine (0.059 g, 0.2 mmol) andbis(1,5-cyclooctadiene)nickel (0.028 g, 0.1 mmol) were mixed in dioxane(1.5 ml) which had been previously mixed with a mixture (0.26 g, 2.0mmol) of 2-thiopheneboronic acid and a boroxine ring compound thereofand water (0.03 g). The reaction mixture was heated to 50° C. and thenstirred at the same temperature for 7 hrs. After the reaction wascompleted, the mixture was left to cool to room temperature andinsoluble substances were filtered off. The filtrate was subjected tocolumn chromatography purification to obtain(L)-N-(t-butyloxycarbonyl)-4-(thiophen-2-yl)phenylalanine methyl ester(0.20 g, yield 56%) as pale yellow crystals.

Example 9

[0334]

[0335] Under a nitrogen atmosphere,(L)-N-(t-butyloxycarbonyl)-O-(p-toluenesulfonyl)tyrosine methyl ester(0.45 g, 1.0 mmol), cesium carbonate (0.65 g, 2.0 mmol),tricyclohexylphosphine (0.059 g, 0.2 mmol) andbis(1,5-cyclooctadiene)nickel (0.028 g, 0.1 mmol) were mixed in dioxane(1 ml) which had been previously mixed with a mixture (0.33 g, 2.0 mmol)of 4-acetylphenylboronic acid and a boroxine ring compound thereof andwater (0.02 g). The reaction mixture was heated to 70° C. and thenstirred at the same temperature for 8 hrs. After the reaction wascompleted, the mixture was left to cool to room temperature andinsoluble substances were filtered off. The filtrate was subjected tocolumn chromatography purification to obtain(L)-N-(t-butyloxycarbonyl)-4-(4-acetylphenyl)phenylalanine methyl ester(0.33 g, yield 89%) as white crystals.

Example 10

[0336]

[0337] Under a nitrogen atmosphere,N-(t-butyloxycarbonyl)-O-(p-toluenesulfonyl)-m-tyrosine methyl ester(0.45 g, 1.0 mmol), cesium carbonate (0.65 g, 2.0 mmol),tricyclohexylphosphine (0.059 g, 0.2 mmol),bis(1,5-cyclooctadiene)nickel (0.028 g, 0.1 mmol) and2,6-dimethoxyphenylboronic acid (0.36 g, 2.0 mmol) were mixed in dioxane(1 ml). The reaction mixture was heated to 60° C. and then stirred atthe same temperature for 2 hrs. After the reaction was completed, themixture was left to cool to room temperature and insoluble substanceswere filtered off. The filtrate was subjected to column chromatographypurification to obtainN-(t-butyloxycarbonyl)-3-(2,6-dimethoxyphenyl)phenylalanine methyl ester(0.39 g, yield 93%) as white crystals.

Example 11

[0338]

[0339] Under a nitrogen atmosphere, methylN-(t-butyloxycarbonyl)-2-amino-2-(4-toluenesulfonyloxyphenyl)acetate(0.44 g, 1.0 mmol), cesium carbonate (0.65 g, 2.0 mmol),tricyclohexylphosphine (0.059 g, 0.2 mmol),bis(1,5-cyclooctadiene)nickel (0.028 g, 0.1 mmol) and2,6-dimethoxyphenylboronic acid (0.36 g, 2.0 mmol) were mixed in dioxane(1 ml). The reaction mixture was heated to 70° C. and then stirred atthe same temperature for 9 hrs. After the reaction was completed, themixture was left to cool to room temperature and insoluble substanceswere filtered off. The filtrate was subjected to column chromatographypurification to obtain methylN-(t-butyloxycarbonyl)-2-amino-2-[4-(2,6-dimethoxyphenyl)phenyl]acetate(0.29 g, yield 72%) as pale yellow oil.

Example 12

[0340]

[0341] Under a nitrogen atmosphere, methylN-(t-butyloxycarbonyl)-3-amino-3-(4-toluenesulfonyloxyphenyl)propionate(0.45 g, 1.0 mmol), cesium carbonate (0.65 g, 2.0 mmol),tricyclohexylphosphine (0.059 g, 0.2 mmol),bis(1,5-cyclooctadiene)nickel (0.028 g, 0.1 mmol) and2,6-dimethoxyphenylboronic acid (0.36 g, 2.0 mmol) were mixed in dioxane(1 ml). The reaction mixture was heated to 50° C. and then stirred atthe same temperature for 2 hrs. After the reaction was completed, themixture was left to cool to room temperature and insoluble substanceswere filtered off. The filtrate was subjected to column chromatographypurification to obtain methylN-(t-butyloxycarbonyl)-3-amino-3-[4-(2,6-dimethoxyphenyl)phenyl]propionate(0.34 g, yield 83%) as colorless oil.

Comparative Example 1

[0342]

[0343] Under a nitrogen atmosphere,(L)-N-(t-butyloxycarbonyl)-O-(p-toluenesulfonyl)tyrosine methyl ester(0.90 g, 2.0 mmol), 2,6-dimethoxyphenylboronic acid (0.55 g, 3.0 mmol),cesium carbonate (1.30 g, 4.0 mmol) andtetrakis(triphenylphosphine)palladium (0.23 g, 0.2 mmol) were mixed indioxane (2 ml). The reaction mixture was heated to 50° C. and thenstirred at the same temperature for 5 hrs. After the reaction wascompleted, the mixture was left to cool to room temperature andinsoluble substances were filtered off. The filtrate was subjected toliquid chromatography to analyze(L)-N-(t-butyloxycarbonyl)-4-(2,6-dimethoxyphenyl)phenylalanine methylester in the filtrate. As the result, the reaction yield was 0% and therecovery percentage of the starting material was 96%.

Comparative Example 2

[0344]

[0345] Under a nitrogen atmosphere,(L)-N-(t-butyloxycarbonyl)-O-trifluoromethanesulfonyltyrosine methylester (0.31 g, 0.7 mmol), 2,6-dimethoxyphenylboronic acid (0.19 g, 1.1mmol), cesium carbonate (0.46 g, 1.0 mmol) andtetrakistriphenylphosphine palladium (0.082 g, 0.07 mmol) were mixed indioxane (7 ml). The reaction mixture was heated to 100° C. and thenstirred at the same temperature for 5 hrs. After the reaction wascompleted, the mixture was left to cool to room temperature andinsoluble substances were filtered off. The filtrate was subjected toliquid chromatography to analyze(L)-N-(t-butyloxycarbonyl)-4-(2,6-dimethoxyphenyl)phenylalanine methylester in the filtrate. As the result, the reaction yield was 63% and therecovery percentage of the starting material was 0%. Furthermore, theoptical purity of the product was 79.5% ee.

Example 13

[0346]

[0347] Protection of a carboxylic acid moiety (synthesis of Compound 2)

[0348] L-tyrosine 1 (181.2 g, 1.0 mol) was suspended in methanol (1268g), and thionyl chloride (428.3 g, 3.6 mol) was added dropwise theretoat 40° C. over 2 hrs. After further keeping at 40° C. for 3 hrs, thereaction mass was concentrated to about one third of the volume underreduced pressure. To the concentrate mass was added dropwise toluene(1268 g) at 40° C. over 1.5 hrs. After keeping at 0° C. for 1 hr,precipitates were filtered and dried under reduced pressure to giveL-tyrosine methyl ester hydrochloride 2 (208.7 g, yield 90.1%) as whitecrystals.

[0349] Protection of an Amino Group (Synthesis of Compound 3)

[0350] L-tyrosine methyl ester hydrochloride 2 (104.3 g, 0.45 mol) anddi-t-butylcarbonate (DBC, 98.2 g, 0.45 mol) were suspended in toluene(521.3 g), and triethylamine (50.1 g, 0.495 mol) was added dropwisethereto at 20° C. over 1.5 hrs. After further keeping at 20° C. for 4hrs, the reaction mass was washed with 5% hydrochloric acid (328.1 g)and 5% aqueous sodium bicarbonate (378.1 g). The toluene solution thusobtained was dried over suitable amount of magnesium sulfate and thenconcentrated to about a half of the volume under reduced pressure. Tothe concentrate was added dropwise n-hexane (329.5 g) at roomtemperature over 1 hr. After keeping at 0° C. overnight, precipitateswere filtered and dried under reduced pressure to give N-Boc-L-tyrosinemethyl ester 3 (126.9 g, yield 95.5%) as white crystals.

[0351] Tosylation of an Aromatic Hydroxyl Group (Synthesis of Compound4)

[0352] N-Boc-L-tyrosine methyl ester 3 (103 g, 0.35 mol) and tosylchloride (66.7 g, 0.35 mol) were dissolved in toluene (517 g) and thencooled to 0° C. To the mixture was added dropwise triethylamine (35.5 g,0.35 mol) at 0° C. over 90 min. The mixture was further kept at 0° C.for 4 hrs. The reaction mass was washed with 5% hydrochloric acid (255g) and 5% aqueous sodium bicarbonate (294 g) and then concentrated at35° C. under reduced pressure until the weight of the toluene layerreached to 243 g. After cooling to −10° C., to the concentrate was addeddropwise n-hexane (310 g) over 3 hrs. Deposited crystals was filteredand dried to give N-Boc-O-tosyl L-tyrosine methyl ester 4 (147 g, yield92%) as white crystals.

[0353] Melting point: 78.8 to 79.5° C.

[0354]¹H-NMR δ (CDCl₃) 1.41 (9H, s), 2.45 (3H, s), 2.95-3.13 (2H, m),3.69 (3H, s), 4.51-4.58 (1H, m), 4.99 (1H, d), 6.90 (2H, d), 7.05 (2H,d), 7.31 (2H, d), 7.68 (2H, d)

Example 14

[0355]

[0356] Benzenesulfonic Acid Esterification of an Aromatic Hydroxyl Group(Synthesis of Compound 5)

[0357] N-Boc-L-tyrosine methyl ester 3 (3.0 g, 0.01 mol) andbenzenesulfonyl chloride (1.8 g, 0.01 mol) were dissolved in toluene(14.8 g) and then cooled to 0° C. To the mixture was added dropwisetriethylamine (1.0 g, 0.01 mol) at 0° C. over 35 min. The mixture wasfurther kept at 0° C. for 3 hrs. The reaction mass was washed with 5%hydrochloric acid (7.3 g) and 5% aqueous sodium bicarbonate (8.4 g) andthen concentrated under reduced pressure with a rotary evaporator togive N-Boc-O-benzenesulfonyl-L-tyrosine methyl ester 5 (4.35 g, yield100%) as white solid.

[0358]¹H-NMR δ (CDCl₃)

[0359] 1.41 (9H, s), 2.95-3.12 (2H, m), 3.68 (3H, s), 4.51-4.58 (1H, m),4.95-4.97 (1H, d), 6.90 (2H, d), 7.05 (2H, d), 7.50-7.55 (2H, m),7.64-7.67 (1H, m), 7.80-7.83 (2H, m)

Example 15

[0360]

[0361] Mesylation of an Aromatic Hydroxyl Group (Synthesis of Compound6)

[0362] N-Boc-L-tyrosine methyl ester 3 (29.5 g, 0.1 mol) andtriethylamine (20.2 g, 0.2 mol) were dissolved in toluene (147.7 g) andthen cooled to 0° C. To the mixture was added dropwise methanesulfonylchloride (13.8 g, 0.12 mol) at 0° C. over 40 min. The mixture wasfurther kept at 0° C. for 25 min. The reaction mass was washed with 5%hydrochloric acid (72.9 g) and 5% aqueous sodium bicarbonate (84.0 g),dried over magnesium sulfate, and then concentrated under reducedpressure with a rotary evaporator. After crystallization from theconcentrate mass with n-hexane, precipitated crystals were collected byfiltration and dried to give N-Boc-O-methanesulfonyl-L-tyrosine methylester 6 (36.0 g, yield 96%) as white crystals.

[0363]¹H-NMR δ (CDCl₃)

[0364] 1.41 (9H, s), 2.99-3.19 (5H, m), 3.72 (3H, s), 3.69 (3H, s),4.55-4.62 (1H, m), 5.01 (1H, d), 7.17-7.24 (4H, m)

Example 16

[0365]

[0366] Protection of a Carboxylic Acid Moiety (Synthesis of Compound 8)

[0367] m-Tyrosine 7 (5.0 g, 27.6 mmol) was suspended in methanol (50ml), and thionyl chloride (2.4 ml, 33.1 mmol) was added dropwise theretoat 50° C. over 0.5 hrs. The mixture was further kept at 50° C. for 3hrs. The solvent was distilled off under reduced pressure, and tolueneand ethyl acetate were added to the residue. A resulting solid wascollected by filtration and dried under vacuum to give m-tyrosine methylester hydrochloride 8 (6.4 g, yield 100%).

[0368] Protection of an Amino Group (Synthesis of Compound 9)

[0369] m-Tyrosine methyl ester hydrochloride 8 (6.4 g, 27.6 mmol) anddi-t-butylcarbonate (DBC, 6.3 g, 29.0 mmol) were suspended in toluene(40 ml), and triethylamine (4.2 ml, 30.4 mmol) was added dropwisethereto at 23° C. or below over 0.5 hrs. The mixture was further kept at20° C. for 0.5 hrs to give a solution of N-Boc-m-tyrosine methyl ester 9in toluene.

[0370] Tosylation of an Aromatic Hydroxyl Group (Synthesis of Compound10)

[0371] Subsequently, a solution (15 ml) of tosyl chloride (TsCl, 5.3 g,27.6 mmol) in toluene was added dropwise to the above solution at 20° C.over 0.5 hrs. After cooling to 0° C., to the mixture was added dropwisetriethylamine (3.9 ml, 27.6 mmol) over 0.5 hrs. After keeping at 0° C.to room temperature for 3 hrs, the reaction mixture was washed with 5%hydrochloric acid (80 ml), 5% aqueous sodium bicarbonate (80 ml), water(80 ml) and saturated brine (80 ml), and dried over anhydrous magnesiumsulfate. The solvent was distilled off under reduced pressure. Theresidue was purified by silica gel column chromatography (hexane/ethylacetate=4/1 to 7/2) to give N-Boc-O-tosyl m-tyrosine methyl ester 10(10.4 g, yield 83.8% from compound 8) as white crystals.

[0372]¹H-NMR δ (CDCl₃)

[0373] 1.43 (9H, s), 2.45 (3H, s), 3.03 (2H, m), 3.71 (3H, s), 4.51 (1H,dd), 4.95 (1H, dd), 6.78 to 7.21 (4H, m), 7.30 to 7.70 (4H, m)

Example 17

[0374]

[0375] Protection of a Carboxylic Acid Moiety (Synthesis of Compound 12)

[0376] D-4-Hydroxyphenylglycine 11 (10.1 g, 60.4 mmol) was suspended inmethanol (100 ml), and thionyl chloride (5.2 ml, 72.5 mmol) was addeddropwise thereto at 50° C. over 0.5 hrs. After further keeping at 50° C.for 3 hrs, the solvent was distilled off under reduced pressure, andtoluene and ethyl acetate were added to the residue. A resulting solidwas collected by filtration and dried in vacuo to giveD-4-hydroxyphenylglycine methyl ester hydrochloride 12 (12.5 g, yield95.3%).

[0377] Protection of Amino Group (Synthesis of Compound 13)

[0378] D-4-Hydroxyphenylglycine methyl ester hydrochloride 12 (12.0 g,54.0 mmol) and di-t-butylcarbonate (DBC, 12.4 g, 56.7 mmol) weresuspended in toluene (75 ml), and triethylamine (8.2 ml, 59.0 mmol) wasadded dropwise thereto at 23° C. or below over 0.5 hrs. The mixture wasfurther kept at 20° C. for 0.5 hrs to give a solution ofN-Boc-D-4-hydroxyphenylglycine methyl ester 13 in toluene.

[0379] Tosylation of an Aromatic Hydroxyl Group (Synthesis of Compound14)

[0380] Subsequently, a solution (30 ml) of tosyl chloride (TsCl, 10.3 g,54.0 mmol) in toluene was added dropwise to the above solution at 20° C.over 0.5 hrs, and then cooled to 0° C. To the mixture was added dropwisetriethylamine (7.5 ml, 54.0 mmol) over 0.5 hrs. After keeping at 0° C.to room temperature for 3 hrs, the reaction mixture was washed with 5%hydrochloric acid (160 ml), 5% aqueous sodium bicarbonate (160 ml),water (160 ml) and saturated brine (160 ml), and dried over anhydrousmagnesium sulfate. The solvent was distilled off under reduced pressure.The residue was purified by silica gel column chromatography(hexane/ethyl acetate=4/1) to give N-Boc-D-4-tosylphenylglycine methylester 14 (17.7 g, yield 75.3% from compound 12) as white crystals.

[0381]¹H-NMR δ (CDCl₃)

[0382] 1.42 (9H, s), 2.45 (3H, s), 3.72 (3H, s), 5.29 (1H, d), 5.55 (1H,d), 6.95 to 7.72 (8H, m)

Example 18

[0383]

[0384] Protection of a Carboxylic Acid Moiety (Synthesis of Compound 16)

[0385] 3-Amino-3-(4-hydroxyphenyl)propionic acid (150.91 g, 5 mmol) wassuspended in methanol (2 ml), and thionyl chloride (0.43 ml, 6 mmol) wasadded dropwise thereto at 40° C. over 37 min. After further keeping at40° C. for 2 hrs, the solvent was distilled off under reduced pressureto give oil (1.32 g). The oil was directly used in the next step withoutpurification.

[0386] Protection of an Amino Group (Synthesis of Compound 17)

[0387] The oily substance obtained in the above step anddi-t-butylcarbonate (DBC, 1.15 g, 5 mmol) were suspended in toluene (6.7ml), and triethylamine (4.6 ml, 6 mmol) was added dropwise thereto at20° C. or below over 10 min. The mixture was further kept at 16° C.overnight to give a solution ofN-(t-butyloxycarbonyl)-3-amino-3-(4-hydroxyphenyl)propionic acid methylester hydrochloride 17 in toluene.

[0388] Tosylation of an Aromatic Hydroxyl Group (Synthesis of Compound18)

[0389] Subsequently, a solution (2.7 ml) of tosyl chloride (TsCl, 0.95g, 5 mmol) in toluene was added to the above solution at 13° C. andcooled to −10° C. To the mixture was added dropwise triethylamine (0.7ml, 5 mmol) over 10 min. After keeping at −10° C. to 0° C. for 3 hrs, tothe reaction mixture was added 5% hydrochloric acid (20 ml), and themixture was extracted with ethyl acetate (15 ml×3), washed with water(20 ml) and saturated brine (20 ml), and dried over anhydrous magnesiumsulfate. The solvent was distilled off under reduced pressure. Theresidue was purified by silica gel column chromatography (hexane/ethylacetate=2/1) to giveN-(t-butyloxycarbonyl)-3-amino-3-(4-(p-toluenesulfonyloxy)phenyl)propionicacid methyl ester 18 (1.63 g, yield 72.7% from compound 15) as whitecrystals.

[0390]¹H-NMR δ (CDCl₃)

[0391] 1.42 (9H, s), 2.45 (3H, s), 2.74 (2H, brs) 3.63 (3H, s), 5.01(1H, brs), 5.48 (1H, brs), 6.85 to 7.76 (8H, m)

INDUSTRIAL APPLICABILITY

[0392] According to the process of the present invention, an opticallyactive biaryl compound, which is useful as intermediates formedicaments, agrochemicals, etc., can be produced at low cost and inhigh yield.

1. A process for preparing an optically active biaryl compound of theformula (4):

wherein R* is the same or different and represents a substituent havingat least one asymmetric carbon, R² is the same or different andrepresents a fluorine atom, * a cyano group, a nitro group, asubstituted or unsubstituted linear or branched alkyl group, asubstituted or unsubstituted cycloalkyl group, a substituted orunsubstituted aryl or heterocyclic group, a hydroxyl group, an alkoxylgroup, an aryloxy group, an alkylthio group, an arylthio group, aprotected amino group, a substituted or unsubstituted carbamoyl group, asubstituted or unsubstituted sulfonamide group, a formyl group, analkylcarbonyl group, an arylcarbonyl group, a carboxyl group, analkoxycarbonyl group, or an aryloxycarbonyl group, or the substituentson the adjacent carbon atoms of the benzene ring may be bound each otherand taken together with the benzene ring to form a fused polycyclicaromatic ring, R³ is a substituted or unsubstituted aryl or heteroarylgroup, n₁ is an integer of 1 to 5, n₂ is an integer of 0 to 4, and * isas defined hereinafter, which comprises reacting an aromatic sulfonicacid ester compound of the formula (1):

wherein R¹ is a substituted or unsubstituted alkyl or aryl group, andR², R*, n₁, and n₂ are as defined hereinabove, provided that R¹ is not atrifluoromethyl group, a nonafluorobutyl group or a pentafluorophenylgroup, with an organic boron compound of the formula (2):

wherein R³ is as defined above, and Q¹ and Q² are the same or differentand each is a hydroxyl group, or an alkoxy group having 1 to 4 carbonatoms; or Q¹ and Q² are taken together to form an alkylenedioxy grouphaving 1 to 4 carbon atoms or 1,2-phenylenedioxy group, which isoptionally substituted with an alkyl group having 1 to 4 carbon atoms,or a boroxine ring compound of the formula (3):

wherein R³ is as defined hereinabove, or a mixture of compounds of theformula (2) and the formula (3), at 70° C. or below in the presence of anickel catalyst and a base.
 2. The process according to claim 1, whereinthe substituent R* is a group of the formula (5):

wherein R⁴, R⁵ and R⁶ are different and each is a hydrogen atom, afluorine atom, a substituted or unsubstituted linear or branched alkylgroup, a substituted or unsubstituted cycloalkyl group, a hydroxylgroup, a substituted or unsubstituted alkoxyl group, a substituted orunsubstituted aryloxy group, a cyano group, a protected amino group, aformyl group, a carboxyl group, a substituted or unsubstitutedalkoxycarbonyl group, a substituted or unsubstituted aryloxycarbonylgroup, a substituted or unsubstituted carbamoyl group, a substituted orunsubstituted heterocyclic group, or a substituted or unsubstituted arylgroup, A is a substituted or unsubstituted alkylene group, a substitutedor unsubstituted nitrogen atom, oxygen atom or sulfur atom, n₃ is aninteger of 0 or 1, and the carbon atom marked with * is an asymmetriccarbon atom.
 3. The process according to claim 1 or 2, wherein R¹ is amethyl group, a phenyl group or a p-tolyl group.
 4. The processaccording to any one of claims 1 to 3, wherein a ligand is used inaddition to the nickel catalyst.
 5. The process according to any one ofclaims 1 to 4, wherein the ligand is trialkylphosphine.
 6. The processaccording to any one of claims 1 to 5, wherein the base is alkali metalhydroxide, alkaline earth metal hydroxide, alkali metal carbonate,alkaline earth metal carbonate, alkali metal hydrogencarbonate, alkalimetal alkoxide, alkaline earth metal alkoxide, alkali metal fluoride,tertiary amine or a mixture thereof.
 7. The process according to any oneof claims 1 to 5, wherein the base is cesium carbonate.
 8. The processaccording to any one of claims 1 to 7, wherein the nickel catalyst is azerovalent nickel catalyst.
 9. An optically active compound of theformula (1a):

wherein R¹⁰ is a substituted or unsubstituted alkyl or aryl group, R¹¹is a protecting group for an amino group, R¹² is a protecting group foran amino group, or a hydrogen atom, R¹³ is a substituted orunsubstituted alkyl group, or either R¹¹ or R¹² and R¹³ are takentogether to form a protecting group for amino acid, n₁₁, n₁₂ and n₁₃ areeach independently an integer of 0 or 1, the carbon atom marked with *is an asymmetric carbon atom, provided that R¹⁰ is not a trifluoromethylgroup, a nonafluorobutyl group or a pentafluorophenyl group.
 10. Acomposition comprising the optically active compound of the formula (1a)according to claim 9 and an enantiomer thereof in any ratio.
 11. Thecompound according to claim 9, wherein R¹¹ is a carbamate-typeamino-protecting group, an amide-type amino-protecting group or anN-alkyl type amino-protecting group, and R¹² is a hydrogen atom.
 12. Thecompound according to claim 9, wherein R¹¹ is an acetyl group, atrifluoroacetyl group, a benzyl group, a t-butyloxycarbonyl group, a9-fluorenylmethoxycarbonyl group or a benzyloxycarbonyl group, and R¹²is a hydrogen atom.
 13. The compound according to any one of claims 9 to12, wherein R¹³ is an alkyl group having 1 to 4 carbons or a benzylgroup.
 14. The compound according to any one of claims 9 to 13, whereinR¹⁰ is a methyl group, a phenyl group, a p-nitrophenyl group or ap-methylphenyl group.
 15. A process for preparing the compound of theformula (1a) according to claim 9, which comprises the step of reactinga compound of the formula (12):

wherein n₁₁, n₁₂ and n₁₃ are each independently an integer of 0 or 1,and the carbon atom marked with * is an asymmetric carbon atom, with analcohol compound of the formula (13): R¹³OH  (13) wherein R¹³ is asubstituted or unsubstituted alkyl group, to protect the carboxyl group;the step of introducing a protecting group for an amino grouprepresented by R¹¹ or R¹² to protect the amino group; and the step ofintroducing a R¹⁰SO₂ group by a reaction of the phenolic hydroxyl groupwith a sulfonic acid esterifying agent to accomplish sulfonic acidesterification.
 16. A process for preparing an optically active biarylcompound of the formula (4a):

wherein R*, R², R³, n₁, n₂ and * are as defined hereinbelow, whichcomprises reacting an optically active aromatic sulfonic acid estercompound of the formula (1a):

wherein R¹⁰ is a substituted or unsubstituted alkyl or aryl group, R¹¹is a protecting group for an amino group, R¹² is a protecting group foran amino group, or a hydrogen atom, R¹³ is a substituted orunsubstituted alkyl group, or either R¹¹ or R¹² and R¹³ are takentogether to represent a protecting group for amino acid, n₁₁, n₁₂ andn₁₃ are each independently an integer of 0 or 1, and the carbon atommarked with * is an asymmetric carbon atom, provided that R¹⁰ is not atrifluoromethyl group, a nonafluorobutyl group or a pentafluorophenylgroup, with an organic boron compound of the formula (2):

wherein R³ is an optionally substituted aryl group or heteroaryl group,Q¹ and Q² are the same or different and each is a hydroxyl group or analkoxy group having 1 to 4 carbon atoms, or Q¹ and Q² are taken togetherto form an alkylenedioxy group having 1 to 4 carbon atoms or1,2-phenylenedioxy group, which is optionally substituted with an alkylgroup having 1 to 4 carbon atoms, or a boroxine ring compound of theformula (3):

wherein R³ is as defined hereinabove, or a mixture of compounds of theformula (2) and the formula (3), at 70° C. or below in the presence of anickel catalyst and a base.